Growing Lighting Types and Intensities Lumen A unit of measurement of the total flow of light which is emitted continually from a source. One lumen is equal to the flow of light which is emitted from a very small wax candle. The common 40 Watt incandescent bulb emits some 400 lm (lumen). So the efficiency of that bulb is 400lm/40Watt= 10 lm/watt. LUX = lm/m 2 , the intensity of light which falls on a surface. Colour Temperature - measured in degrees Kelvin, the color of a light's output in relationship to the degree of heat applied to produce the specified colour of light. Daylight is measured around 5000 degrees kelvin If we direct all light from our 40 Watt lamp towards a floor area of 1 square meter the intensity of light on that area will be 400 lux, (400 lumen distributed over 1 square meter, 400/1 lm/m 2 = 400 lux,) which is a little better than moonlight, but far away from the sunlight intensities we need for growing plants. The sun gives some 50 000 lm/m 2 = 50 000 lux at the earth surface on a clear summerday. See the table below. The 40 Watt incandescent lamp is not only too weak for growing plants, it also has too little blue in its spectrum and is far too inefficient. Fluoroscent tubes and HPS and MH lamps are the better choices. Cannabis needs 24 hours of strong light for the first 4-6 weeks of vegetative growth. Then it needs 2 months of 12/12 hours of strong light and very dark, to flower and ripen. If they get less than 30000 lux they will still grow vegetatively but slower. And they will flower less, if at all. Light Requirements of "High Energy" Plants 1000 - 5000 lux Min. necessary for life 10000 - 15000 lux Min. necessary for consistent but sparse growth 20000 - 25000 lux Min. necessary for robust growth 25000 - 30000 lux Max. Efficiency for Sub Tropical varieties 25000 - 50000 lux Max. Efficiency for Equatorial varieties Plants need 25000-50000 lux too grow fast. 90000 lux Max. Sunlight Intensity on Earth's surface This is too much light, it is not good for the plant. Plants subject to intensities at this level or greater are at risk of "solarization," whereby photosynthesis is retarded. This can happen at noon on a clear Tropical summer day, especially at high altitudes. 140000 lux Sunlight above atmosphere (Solar Constant) More advanced theory: Scientific, but has many answers about how and why. Air Temperatures between Cannabis Lighting Types and Intensities http://growinghelp.com/cannabis/lighting_guide.php 2 of 9 8/9/2013 5:05 PM
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Growing Lighting Types and Intensities
Lumen
A unit of measurement of the total flow of light which is emitted continually from a source. One lumen
is equal to the flow of light which is emitted from a very small wax candle.
The common 40 Watt incandescent bulb emits some 400 lm (lumen). So the efficiency of that bulb is
400lm/40Watt= 10 lm/watt.
LUX
= lm/m2, the intensity of light which falls on a surface.
Colour Temperature
- measured in degrees Kelvin, the color of a light's output in relationship to the degree of heat applied
to produce the specified colour of light. Daylight is measured around 5000 degrees kelvin
If we direct all light from our 40 Watt lamp towards a floor area of 1 square meter the intensity of light on
that area will be 400 lux, (400 lumen distributed over 1 square meter, 400/1 lm/m2 = 400 lux,) which is a
little better than moonlight, but far away from the sunlight intensities we need for growing plants.
The sun gives some 50 000 lm/m2 = 50 000 lux at the earth surface on a clear summerday. See the table
below.
The 40 Watt incandescent lamp is not only too weak for growing plants, it also has too little blue in its
spectrum and is far too inefficient. Fluoroscent tubes and HPS and MH lamps are the better choices.
Cannabis needs 24 hours of strong light for the first 4-6 weeks of vegetative growth. Then it needs 2
months of 12/12 hours of strong light and very dark, to flower and ripen. If they get less than 30000 lux they
will still grow vegetatively but slower. And they will flower less, if at all.
Light Requirements of "High Energy" Plants
1000 - 5000 lux Min. necessary for life
10000 - 15000 lux Min. necessary for consistent but sparse growth
20000 - 25000 lux Min. necessary for robust growth
25000 - 30000 lux Max. Efficiency for Sub Tropical varieties
25000 - 50000 lux Max. Efficiency for Equatorial varieties
Plants need 25000-50000 lux too grow fast. 90000 lux Max. Sunlight Intensity on Earth's surface This is
too much light, it is not good for the plant. Plants subject to intensities at this level or greater are at risk of
"solarization," whereby photosynthesis is retarded. This can happen at noon on a clear Tropical summer
day, especially at high altitudes. 140000 lux Sunlight above atmosphere (Solar Constant)
More advanced theory: Scientific, but has many answers about how and why. Air Temperatures between
Cannabis Lighting Types and Intensities http://growinghelp.com/cannabis/lighting_guide.php
2 of 9 8/9/2013 5:05 PM
23C (70F) and 32C (90F) are ideal for growth; beyond 35C (95F) can adversely affect plants, retarding
photosynthesis, and, in extreme cases, can cause leaf burn if a radiant heat source is nearby. Calculating
with lumen, lux and efficiency: The cheapest and easiest solution to the beginner is to use fluoroscent
tubes. The usual ones are 120 cm (48") long, and give at best 4000 lumen. *****Ed Note: If you care to get
a light meter and measure the light from various distances to your flouros, you'll see immediately that you
will want to keep the lights as close to the top of your plants as possible. ***** Your grow room must have at
least these dimensions: 140 cm high (these plants get big, 180 cm is better, 120 cm long (to accomodate
for the tubes), and wide enough, let's say 60cm (2 feet). The easiest is to build an extra wall, made of silver
tarpaulin or wood. This wall is placed 60 cm from a real wall, to create a space of say 200*260*60cm for
use as a greenhouse or rather two. Build the wall and divide the space up into two small rooms. Make
some type of opening, so you can take care of your plants later. Put in ventilation and cover all inside
surfaces with al-foil using a stapler. We want the light to bounce around in there until it finds a green leaf to
do its work in. As much light as possible is needed for the growth of the plants. The ventilation consists of a
12Volt fan which pushes the warm air from the green house through a plastic tube which ends outside the
house to let the warm moist and odors out. Instead of a fake wall you can disguise the green house as a
very big bass speaker, stereo wall, tv-stand, cupboard or whatever. Buy the fluoros in ready-made units or
do it yourself like this: Buy the bare necessities to put up fluoros, that is reactors, lighters, tube holders,
lighter holders, wire.7mm, capacitors and connectors. Most of these devices have pushcontacts, that
means you don't have to solder or screw much, just strip off the insulation from the cable and push it in.
Put up as many tubes as possible in the ceiling of the green house. You might be able to get 6 tubes into
every green house half. Every green house has a floor area of 0.60m*1.30m=0.78m2 With 6*4000 lumen
you get 24000lumen. Divide by 24000lm with 0.78m2 to get 31000 lux, which is good enough.
Use hanging mounts for the tubes, they are cheapest and easiest to use. They also make it easier to pack
the tubes densely in the cieling or hanging at different levels, hanging only in the thin electric cables. If you
manage to get 10 tubes into the top of the green house you get 40000lm/0.78m2= 51300 lux in there.
As another example, let's take one of the most popular hps grow bulbs:
Lumen Watt lm/watt Kelvin Hours Manufacturer, Name
53,000 430 123.3 2000 16k Philips, SON T AGRO
The Son-T-Agro gives out 53000 lumen. If we use a reflector to direct all of that light towards a floor area of
2 m2 we get a light intensity on that area of 53000 lumen/2 m
2, which is 26500 lumen/m
2 (=lux)
We can see in table 3 above that it fits in: "25000 - 30000 lux =Max. Efficiency for Sub Tropical varieties".
We add some daylight fluoros, 6 fluoros a 4000 lumen=24000 lumen. Divide by floor area 2 m2 to get
=12000lumen/m2=12000lux
Together the hps and the fluoros give 26500+12000=38500lux in the 2 m2 big grow room. see table 3:
25000 - 50000 lux Max. Efficiency for Equatorial varieties.
This combination will draw 430Watt+6*40Watt+100Watt in the ballast units, total =530+240=770Watt of
electricity. Our total efficiency is 53 000 + 24 000 lm divided with 770 Watt, which is 77 000 lumen /770
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3 of 9 8/9/2013 5:05 PM
Watt = 100 lm/Watt At 38500 lux we have an illumination which is optimal for growth,
Illumination Chart
Light Intensity (lux) as a Function of Area Illuminated (m2)
Introduction to Indoor Grow Lights for MarijuanaIntroduction to Indoor Grow Lights for MarijuanaIntroduction to Indoor Grow Lights for MarijuanaIntroduction to Indoor Grow Lights for Marijuana
Are you ready to get starting growing marijuana with
indoor grow lights?
Marijuana plants are not like your average indoor
houseplant.
They live out their whole lives (seed to harvest) in just one yearone yearone yearone year, and they
need to get a lot of light a lot of light a lot of light a lot of light in order to make enough energy to grow big,
then produce buds (marijuana flowers).
Generally, you will need special types of lighting to grow marijuana,
though some regular house lights can work too, if you know what to do.
Please note: Incandescent light bulbs are NOT suitable for growing
marijuana!
Of course, if you plan on growing marijuana
outdoorsoutdoorsoutdoorsoutdoors, the sun is generally all the light
you need to grow your own weed. When
growing outdoors, your marijuana needs to
grow in a sunny spot with plenty of direct
sunlight throughout the whole day. For best
results, plants should get strong sunlight
for 8+ hours each day.
Yet as an indoor grower, there's a few
things you should know about lights and
growing marijuana. You see, marijuana is a
short-day plant, which means that
marijuana plants don't start making buds until their "days" become short
enough.
The length of time that your cannabis gets light and darkness eachThe length of time that your cannabis gets light and darkness eachThe length of time that your cannabis gets light and darkness eachThe length of time that your cannabis gets light and darkness each
day will determine when it starts flowering (making buds). Mostday will determine when it starts flowering (making buds). Mostday will determine when it starts flowering (making buds). Mostday will determine when it starts flowering (making buds). Most
marijuana plants need long marijuana plants need long marijuana plants need long marijuana plants need long (12+ hours) (12+ hours) (12+ hours) (12+ hours) nights to start flowering.nights to start flowering.nights to start flowering.nights to start flowering.
The major factor that determines when most marijuana plants start
flowering is the length of the photoperiod, length of the photoperiod, length of the photoperiod, length of the photoperiod, or how long the plant
receives light and total darkness each day....
OutdoorsOutdoorsOutdoorsOutdoors, the sun is in charge of when your plants start budding. When
the days start getting shorter as winter approaches, your marijuana plants
will naturally start flowering.
IndoorsIndoorsIndoorsIndoors, you are in control of when your plant starts
budding. You do this by adjusting the plant's daily light
schedule, usually by hooking up your grow lighs to an
Some strains of cannabis are "auto-flowering" "auto-flowering" "auto-flowering" "auto-flowering" which means that they
ignore the length of the photoperiod, but these strains are rare to come
across unless you specifically buy auto-flowering marijuana seeds. Where do I
buy seeds?
Auto-flowering plants tend to be less potent than non-auto-flowering
plants, but not always.
The color spectrum of the light color spectrum of the light color spectrum of the light color spectrum of the light your plants get will also have a small
effect on their vegetative and flowering stages. Light that's closer to the
blue spectrum simulates Spring/Summer while light in the red/yellow
spectrum simulates sunlight from the Fall/Winter.
The color spectrum of your grow light will have a much smaller effect on
your plants than the photoperiod, and I wouldn't worry too much about it
if you're a beginner. As long as you buy a grow light that is meant for
growing weed (like all the ones listed on this page), then your color
spectrum will be close enough to get great results. After you have a few
successful grows under your belt, you can start to worry about
maximizing your light's color spectrum.
(Where can I safely buy marijuana seeds online?)
Wait! I'm Still Confused About Photoperiods. How Much Light Does My Plant Need
To Start Making Buds?
Tell Me More About the Effect of Light Color Spectrum on Growing Marijuana
The big advantage of using indoor growlights is they effectively control all
aspects of your plant's light.
Because of this total control over light when growing indoors, indoor buds can often be even more tasty and
potent than similar marijuana buds grown outside.
The most common types of lights used indoor with marijuana is HighHighHighHigh
Intensity Discharge (HID) lightsIntensity Discharge (HID) lightsIntensity Discharge (HID) lightsIntensity Discharge (HID) lights such as High Pressure Sodium (HPS)High Pressure Sodium (HPS)High Pressure Sodium (HPS)High Pressure Sodium (HPS)
and Metal Halide (MH) lightsMetal Halide (MH) lightsMetal Halide (MH) lightsMetal Halide (MH) lights.
These grow lights are powerful and proven to provide great yields,
though they use quite a bit of energy and produce a lot of heat for a small
grow space.
WIth HID lights, you will get the best results of any grow light, but will
generally also have to install some sort of exhaust system to properly deal
with the heat.
You can also grow marijuana plants using Compact Florescent LightsCompact Florescent LightsCompact Florescent LightsCompact Florescent Lights
(CFLs)(CFLs)(CFLs)(CFLs) and LED grow lightsLED grow lightsLED grow lightsLED grow lights which both use less power and produce less
heat than HID lights.
Each type of light system has their pros and cons, but you will need to
And Now For The Complete Marijuana Grow Light Breakdown...And Now For The Complete Marijuana Grow Light Breakdown...And Now For The Complete Marijuana Grow Light Breakdown...And Now For The Complete Marijuana Grow Light Breakdown...
Metal Halide (MH) & High Pressure Sodium (HPS) Lights
The two main types of High Intensity Discharge (HID) lights used for
growing marijuana are Metal HalideMetal HalideMetal HalideMetal Halide and High Pressure Sodium High Pressure Sodium High Pressure Sodium High Pressure Sodium lights.
MH / HPS lights are generally considered the golden standard for growing marijuana.
View Full Step-By-Step Picture Tutorial on How to Set Up
Metal Halide(MH) and High Pressure Sodium (HPS) Grow Lights
HID lights will help you produce great yields. Many growers believe thatMany growers believe thatMany growers believe thatMany growers believe that
the Metal Halide/HPS grow light combination will acheive the bestthe Metal Halide/HPS grow light combination will acheive the bestthe Metal Halide/HPS grow light combination will acheive the bestthe Metal Halide/HPS grow light combination will acheive the best
cannabis yields,cannabis yields,cannabis yields,cannabis yields, though other types of grow lights can be close
contenders.
Though HPS or MH/HPS grow lights consistently producte great yields,
they use more electricity and produce more heat than pretty much any
other type of grow lights. Therefore you will most likely have to set up
fans and ducting to properly vent out all the heat. Some growers even use
these lights to help heat up their homes in the winter.
Metal Halide (MH) lights produce light that has more blues and whites in it
than the sunlight's natural light spectrum, which makes it most suitable
for use during the vegetative stage of your marijuana plants.
Metal Halide (MH) for the Vegetative StageMetal Halide (MH) for the Vegetative StageMetal Halide (MH) for the Vegetative StageMetal Halide (MH) for the Vegetative Stage
Many growers use Metal Halide lights for the
vegetative stage of their marijuana plants.
Young marijuana plants explode with green, healthy
growth when exposed to MH grow lights.
Metal Halide grow lights can be used for the entire
lifespan of a marijuana plant, but if you must choose
just one, most growers choose to use HPS for the whole grow.
Metal Halide bulbs produce light in the blue spectrum, which mimics the
sunlight during the Spring and Summer, and gives young vegetating
plants exactly what they need.
This blue-tinted light causes your plants to grow fast vegetative growth
(stems, branches, and leaves only), and encourages young plants to grow
short and bushyshort and bushyshort and bushyshort and bushy.
It's possible to skip the Metal Halide bulb and use a High Pressureuse a High Pressureuse a High Pressureuse a High Pressure
Sodium (HPS) bulb for your whole growSodium (HPS) bulb for your whole growSodium (HPS) bulb for your whole growSodium (HPS) bulb for your whole grow. If you can only afford one bulb
and have to choose between MH and HPS, always choose HPS.
HPS grow lights produce light that is perfect for use during the flowering
stage of your marijuana plants. The light that an HPS emits will appear
amber/yellow or even pinkish. HPS bulbs are often used in street lights or
to light huge areas like stadiums.
High Pressure Sodium (HPS) for the Flowering StageHigh Pressure Sodium (HPS) for the Flowering StageHigh Pressure Sodium (HPS) for the Flowering StageHigh Pressure Sodium (HPS) for the Flowering Stage
Most growers who started out with MH switch to High
Pressure Sodium bulbs for the flowering stage.
This takes advantage of the optimal light spectrum
needed by your plants during the flowering stage to
produce big, potent buds.
High Pressure Sodium grow lights produce a pinkish
yellow light with lots of light in the red/orange spectrum.
This yellowish light causes plants to initially stretch upwards in a last
spurt of growth, and from then on to focus all their energy into growing
Choosing your MH or HPS Grow LightsChoosing your MH or HPS Grow LightsChoosing your MH or HPS Grow LightsChoosing your MH or HPS Grow Lights
If it's your first time growing with an MH or HPS grow light, I recommend
buying your bulb(s), ballast, and hood (reflector) together as a settogether as a settogether as a settogether as a set, like
the one pictured to the left.
This just makes things easy and lets you focus on growing marijuana
instead of worrying about matching bulbs, ballasts, and hoods together.
The most important thing to remember is that the type of bulb and thethe type of bulb and thethe type of bulb and thethe type of bulb and the
type of ballast always need to match each othertype of ballast always need to match each othertype of ballast always need to match each othertype of ballast always need to match each other. In practice, this is
really easy and clear; you just match up the numbers. More on that in a
second.
For HID grow lights, 150-250 watt bulbs are suitable for 1-3 plants and
will cover an area measuring 3 feet square (3x3).
I generally recommend against getting an HID bulb that is less thanI generally recommend against getting an HID bulb that is less thanI generally recommend against getting an HID bulb that is less thanI generally recommend against getting an HID bulb that is less than
400W400W400W400W, as they're just not efficient and you'll often get better results in
that small a space with CFLs, LEDs, or fluorescent lighting such as a T5.
Many growers choose to get a 400 and 600 watt bulb/ballast which is
suitable for 4-12 plants.
You can get 1000 watt (or more) bulbs, and this is especially common
with high-yield and commercial operations, which can use light movers,
lots of CO2, and other relatively expensive tactics to get more yield out of
a certain small indoor area.
For a small-time grower, it is often more practical to get 400W or 600W
grow lights, as these produce much less heat than 1000W bulbs. If you
need multiples of 400W and 600W MH/HPS grow lights, they can often be
easier to space out evenly in a small grow space than bigger wattage
bulbs.
Of all the different types of HPS lights, the 600W HPS light is the most600W HPS light is the most600W HPS light is the most600W HPS light is the most
efficient as far as how much light they produce for how muchefficient as far as how much light they produce for how muchefficient as far as how much light they produce for how muchefficient as far as how much light they produce for how much
electricity they useelectricity they useelectricity they useelectricity they use.
Still not sure which HID grow light?
Walk me through the process of picking out the right MH or HPS Grow
Light for my situation.
If you must choose just one type of HID lightIf you must choose just one type of HID lightIf you must choose just one type of HID lightIf you must choose just one type of HID light, most growers choose to
use HPS lights from beginning to end of your marijuana plant's life cycle.
Just be gentle during the seedling stage! HPS lights also tend to cause
young vegetative marijuana plants to stretch, so you may want to employ
some growth control methods so your plants grows exactly the way you
As far as maintenance and setup, Metal Halide and High Pressure Sodium
bulbs are pretty much the same.
Show me how to set up my MH/HPS grow lights step-by-step
All HID lights (Metal Halide or HPS) require that you have a...All HID lights (Metal Halide or HPS) require that you have a...All HID lights (Metal Halide or HPS) require that you have a...All HID lights (Metal Halide or HPS) require that you have a...
Ballast Ballast Ballast Ballast (which usually plugs into a standard power socket)
buying all the pieces separately. There's nothing more frustrating than
trying to fit parts together that just don't quite work!
By the whole system I mean the bulb, ballast and hood (reflector).By the whole system I mean the bulb, ballast and hood (reflector).By the whole system I mean the bulb, ballast and hood (reflector).By the whole system I mean the bulb, ballast and hood (reflector).
You can purchase a system that suits all your needs, and you can be
confident that everything will fit together properly.
I strongly recommend against against against against buying a used light system to save a few bucks.
Some growers don't take good care of their lights. Additionally, after HID
bulbs have been used for a while, they will start to consume more
electricity while also producing less light.
When this happens, you will need to replace the bulbs anyway.
Why start with someone else's half-used equipment?
There are many cheap options available for new, high-quality equipment,
but you need to know the right places to look.
Help me find the right MH or HPS grow light for my budget
Compact Florescent Lights (CFLs)
The term "CFL" is short for "Compact Florescent Light."
These lights are commonly sold at home improvement
stores, and even in grocery stores.
Many people don't realize that these regular household light
bulbs actually provide a spectrum of light that your
cannabis plants can use to grow!
You will need two or three 42w(150w incandescent equivalent) CFLs per
plant to startto startto startto start.
These lights are easily found at stores such as Home Depot and Walmart,
or that can be purchased online.
You can get lower or higher wattage bulbs, but I like bulbs close to the
40w range because they produce a lot of light, but are still a small,
Any part of the plant that is further away then 1-2 feet from the
fluorescent grow lights is not getting an optimum amount of light.
With the new high output lights such as the T5With the new high output lights such as the T5With the new high output lights such as the T5With the new high output lights such as the T5, fluorescent lights can
be used until the plants are about 24 inches tall, which is just enough to
grow a very short plant through to the flowering stage when you control
your marijuana plant's growth through the vegetative stage.
The great thing about fluorescent grow lights is that
they don't get hot at all, and they can be kept 1-4
inches from the tops of the plants at all times without
having to worry about burning your cannabis leaves
or buds.
The other great thing about fluorescent lights is that they are moremoremoremore
energy efficientenergy efficientenergy efficientenergy efficient than many other types of lights, and therefore won't
make a huge mark on your electricity bill.
There are many different levels of fluorescent grow lights including the
T5, the T8 and the T12. I strongly suggest sticking with the T5 style of
fluorescent grow lights because they are the most advanced, give off the
most amount of light per watt used, and are specifically designed to be
able to support taller plants up to 24 inches.
For optimal results, choose fluorescent light bulbs that are labeled either
as "Cool White" or "Cool" colored for vegetative growth (Cool White is also
labeled as "6500k" colored.
Choose bulbs that are "Warm White" or "Soft White" colored (usually
labeled as "2500K" or "3000K") for flowering growth.
However, you can use either type of lights during either stage and still get
good results. I have also heard of people using "Daylight" (5000K) bulbs
with success.
Check to see that the bulbs you are getting are labeled as "High Output."
This ensures that you're getting the most lumens (light) from your bulbs.
LED Grow Lights
You may or may not know about the LED grow lightLED grow lightLED grow lightLED grow light craze among
marijuana growers.
LED grow lights use less energy and generate much less heat than
standard HID grow lights, so there's good reason for all the attention.
Today, I'll be answering the following questions:
Why is there so much controversy about whether LED grow lightsWhy is there so much controversy about whether LED grow lightsWhy is there so much controversy about whether LED grow lightsWhy is there so much controversy about whether LED grow lights
Which companies, if any, have the best LED grow lightsWhich companies, if any, have the best LED grow lightsWhich companies, if any, have the best LED grow lightsWhich companies, if any, have the best LED grow lights
(specifically for growing marijuana)?(specifically for growing marijuana)?(specifically for growing marijuana)?(specifically for growing marijuana)?
2.
Some people say LEDs work great for growing marijuana, while others
claim LED grow lights are junk and can't be used to grow anything.
The truth is that both sides are right.
Now, I'm talking about grow lights made of light emitting diodeslight emitting diodeslight emitting diodeslight emitting diodes,
commonly known as LEDs. You may have seen ads for these lights, which
often resemble UFOs, and claim to be the growing technology of the
future.
First invented in 1927, no one could find any practical use for these tiny
lights until 1962, when LEDs first hit the scene in 1962 as glowing red
indicators on electronics.
After that, LED development has proceeded rapidly.
LEDs, which were originally tiny and dim, have doubled in efficiency anddoubled in efficiency anddoubled in efficiency anddoubled in efficiency and
light output about once every 36 monthslight output about once every 36 monthslight output about once every 36 monthslight output about once every 36 months since the 1960s.
As you probably know, humans have tried growing plants with just about
every type of artificial light we've ever created, and LEDs are no
exception.
Which has all led to the development of LED grow lightsLED grow lightsLED grow lightsLED grow lights.
At first, no one could successfully grow anything using LEDs. Each
individual LED is relatively small and produces only a specific
wavelength(color) of light, and we couldn't seem to successfully replicate
the proper strength and color of sunlight.
But through trial and error, we've now developed some wickedly effective
LED grow lights.
And LED grow light systems have some pretty sweet benefits:And LED grow light systems have some pretty sweet benefits:And LED grow light systems have some pretty sweet benefits:And LED grow light systems have some pretty sweet benefits:
Extremely efficient, using less electricity than other grow lights
LED light systems run cool and many models do not need anything extra to control heat
Most LED light systems can be plugged directly into a regular power outlet, and don't
need a ballast or special light socket like many other grow lights.
Some growers claims that marijuana buds grown under LEDs contain more THC and other
cannabinoids (which may be because marijuana produces stronger buds when slightly
stressed)
Now, it's been proven that LEDs can be used to grow marijuana plants
from the beginning to the end of their life cycle.
I know this is true because I have personally have grown marijuana plants
from seed to harvest with a Lighthouse Hydro BlackStar 135 Watt LED
grow light system.
My search for LEDs started because I live in an area where heat can be an
issue. I am also a small scale grower who would like to still have a
presentable house for guests.
Where I was living at the time, I didn't want to have install ducting for
ventilation or anything like that, which made HID lights pretty much out of
the question for me.
Based on the experiences of some of my fellow growers, I
discovered many LED grow light systems just don't work for growingmany LED grow light systems just don't work for growingmany LED grow light systems just don't work for growingmany LED grow light systems just don't work for growing
marijuana.marijuana.marijuana.marijuana.
After doing some research, I got my Lighthouse Hydro BlackStar 135
Watt LED grow light in 2012. I got a second one a few months later, I've
grown 3 crops in total under just these BlackStar panels, growing two
small plants under each UFO LED Grow Light panel.
My yields under the Lighthouse Hydro Blackstar were a bit smaller than
normal and throughout the grow my plant leaves appeared a bit beat up
(got occasional spots, brown marks, and other signs of light stress,
especially the leaves close to the LEDS), but the buds produced with the
Lighthouse Hydro Blackstar were always dank, ultra-poten and stickydank, ultra-poten and stickydank, ultra-poten and stickydank, ultra-poten and sticky.
The incredible quality of the buds kept me trying to find ways to up the
total yields.
Plus I was saving money on my electricity bill (electricity use with the
Lighthouse Hydro Blackstar LED Grow Light was minimal), and there was
no heat to speak of, which really simplified the heat situation in my tiny,
tiny closet.
I was pretty satisfied with the results.
Then I had the pleasure of running into other growers who have usedThen I had the pleasure of running into other growers who have usedThen I had the pleasure of running into other growers who have usedThen I had the pleasure of running into other growers who have used
specific models of LED grow lights that work FANTASTICspecific models of LED grow lights that work FANTASTICspecific models of LED grow lights that work FANTASTICspecific models of LED grow lights that work FANTASTIC.
So LED grow lights can work, but at the same time, it is true that some
work much better than others. And there really are dishonest companies
out there who probably just slapped together a bunch of LEDs, which no
consideration to what's really needed to grow a plant, and these LED grow
lights will never grow anything, no matter what you do.
Not too long ago..Not too long ago..Not too long ago..Not too long ago..
LED grow lights used to always come as a panel with several 1 watt LED bubs. So in the old days, if you got a 90W LED grow
light, it used to have 90 1W LED bulbs.
These days, it's much more common to see LED grow lights with an array
of 3W and 5W bulbs.
Something to keep in mind is that the "real" energy output of LEDs is
actually only 2/3 of the stated output. In other words, a "3W" LED really
only puts out 2W. That's why you'll sometimes see confusing numbers
like a 90W LED Grow light (with 45 X 3W LEDs).
These 3W and 5W LED bulbs are widely considered to have deeper
penetration than the old-fashioned 1W bulbs. Therefore it's
recommended that you get an LED grow light with 3W bulbs or bigger.
While each individual bulb doesn't produce a
whole lot of light, LED bulbs can be
manufactured to produce light that is in the
spectrum that the plant needs to grow.
With other grow lights, while they may be
powerful, but a lot of the light produced is in a
spectrum that the plant just can't use to grow.
Because the newer LED grow lights are being made to produce only the
needed light spectrum without all that extra, they use very little
electricity.
The main benefit of LED lights is they can be more efficient thanThe main benefit of LED lights is they can be more efficient thanThe main benefit of LED lights is they can be more efficient thanThe main benefit of LED lights is they can be more efficient than
other grow lights, meaning they use less energy and produce lessother grow lights, meaning they use less energy and produce lessother grow lights, meaning they use less energy and produce lessother grow lights, meaning they use less energy and produce less
heat.heat.heat.heat.
However, LED grow lights are relatively new, and they have a pretty poor
reputation on the internet for growing marijuana. Some people seem to
report good results with LEDs, while others claim they don't work at all.
The truth is that some models work great, while others just don't work for
growing marijuana. It's hard to tell which is which unless you just try the
different models.
I live in an area where heat can be an issue and I am also a small scale
grower who would like to still have a presentable house for guests.
When I first started growing, I didn't want to have install ducting for
ventilation or anything like that, which made HID lights pretty much out of
bigger 105W CFL bulbs in an attempt to step up my growing game (not
recomended!).
Still not wanting to have to invest in an exhaust system, I became
interested in LED grow lights because they seemed to be even better than
CFLs as far as heat output and electricity use.
Another thing that attracted me to LEDs had to do with how far away the
lights needed to be from the plants.
One of the nuisances with CFLs is that you need to keep the bulbs only
2-4 inches away from the plant at all times for optimal growth. If the bulb
is further away, your plants don't get much usable light. If the lights are
closer than 2 inches, they will literally burn the leaves of the plants
because of the heat of the bulb.
Having to keep your lights in the 2-4 inch distance range can be
inconvenient if your plants are growing rapidly or if you need to be away
from your plants for a few days.
Because LEDs barely produce any heat, it doesn't matter as much if the
plant grows into the lights because the LEDs don't produce enough heat
to burn the leaves.
Because of all the benefits, I knew that I needed to at least try an LED
grow light panel.
See an entire grow (seed to harvest) with LED grow lightsSee an entire grow (seed to harvest) with LED grow lightsSee an entire grow (seed to harvest) with LED grow lightsSee an entire grow (seed to harvest) with LED grow lights
I would like to share a cheaper brand of LED Grow Light that has also been proven to workcheaper brand of LED Grow Light that has also been proven to workcheaper brand of LED Grow Light that has also been proven to workcheaper brand of LED Grow Light that has also been proven to work
great for growing marijuanagreat for growing marijuanagreat for growing marijuanagreat for growing marijuana, so you can skip the trial and error.
Lighthouse Hydro BlackStar 135W LED Grow LightLighthouse Hydro BlackStar 135W LED Grow LightLighthouse Hydro BlackStar 135W LED Grow LightLighthouse Hydro BlackStar 135W LED Grow Light
(3W Chipset)
Learn more about the Hydro Blackstar
Hydro BlackStar Verdict:
Great for the small-scale grower who wants to grow 1-2 plants in
a closet
Price:Price:Price:Price: About $180
ProsProsProsPros: Low heat, low electricity use, 1 year warranty, incredible quality of
buds produced (seriously the potency is 10/10), can grow two plants with
one Hydro Blackstar panel
ConsConsConsCons: Smaller-than-average yields, somewhat airy buds, any leaves
closer than 15" to the light can show signs of light stress.
Here are some pictures of the plants which were grown primarily under
the Hydro Blackstar panel. The top three show the plants a month before
harvest, and the bottom two photos are from the day of the harvest. The
purple pictures show what the buds look like under the LED lights. Click
on any of the thumbnails to see a bigger version!
Close-up of the trichromes on one the buds growing under the
135W Blackstar LED Grow Light Panel (3W chipset)
See a complete medical marijuana grow under LED grow lights
Read full article on induction grow lights for marijuana
There are many different induction grow lightsinduction grow lightsinduction grow lightsinduction grow lights appearing on the market
today. These “new” grow lights are supposedly longer-lasting and more
efficient than any other grow light.
But what are induction grow lights, and do the claims live up to the hype?
Induction lights are unique because they use inductioninductioninductioninduction
or electromagnetic fieldselectromagnetic fieldselectromagnetic fieldselectromagnetic fields to transfer power instead of electrical
connection or electrodes.
This technology has recently become more popular in recent years, but
has actually been around for a long time. The idea of electrodeless lights
(induction lighting) came from the famous inventor Nikola TeslaNikola TeslaNikola TeslaNikola Tesla in the
late 1800s.
Lights that this technology are called by many names, depending on the
company and how the light gets put together.
Some names for induction lighting include...
full spectrum plasma lights
sulphur plasma grow lights
MPS grow lights
sulphur lamps
High Efficiency Plasma lamps
HEP lighting
magnetic induction grow lights
electrodeless lamp
electrodeless vacuum tube
fluorescent induction lamps
and probably lots of other names...
Biggest Benefits of Induction Grow LightsBiggest Benefits of Induction Grow LightsBiggest Benefits of Induction Grow LightsBiggest Benefits of Induction Grow Lights
No electrodes means a longer life: Induction Grow Lights can
theoretically be run for up to 100,000 hours
Induction lights don’t lose light intensity as fast as MH or HPS grow
lights, they stay close to their full initial brightness even after
running for tens of thousands of hours.
Because these lights last for so long, they are popular for stadium
lighting, street lights, and other types of lighting where bulbs are
difficult or expensive to replace
Yet are the new generation of induction grow lights ready forYet are the new generation of induction grow lights ready forYet are the new generation of induction grow lights ready forYet are the new generation of induction grow lights ready for
Magnetic Induction grow lights seem to be the “hot” type of induction
grow lights on the market today.
The reports I’ve been receiving seem to indicate that the current magnetic
induction grow lights work in situations where fluorescent grow lights
work well. This is because a magnetic induction grow light is basically an
“electrodeless” fluorescent light.
In other words, magnetic induction grow lights are almost the same thing
as a regular fluorescent light (like a T5 or CFLs), only the use induction
instead of electrodes to supply energy to the bulb.
This means that these lights will last longer than fluorescent grow lights,
with few other major benefits.
Magnetic induction grow lights seem to work very well as a supplement to
sunlight or other grow lights, or can be used by themselves.
Should You Go Out and Invest In Magnetic Induction Grow Lights?Should You Go Out and Invest In Magnetic Induction Grow Lights?Should You Go Out and Invest In Magnetic Induction Grow Lights?Should You Go Out and Invest In Magnetic Induction Grow Lights?
Remember, magnetic induction grow lights are basically the same thing as
fluorescent lights without electrodes. No matter what sellers try to say
otherwise, don’t fall for some of the outrageous marketing claims!
If you’re looking for a magical grow light that doesn’t produce any heat,
uses next to no electricity, and produces humongous yields compared to
LEDs, MH, or HPS grow lights, then you’re kidding yourself. Magnetic
induction grow lights just aren’t what you’re looking for.
But...
If you’re looking for a type of grow light that is low heat, uses a relatively
low amount of electricity, has a good form factor for your grow area and
you hate replacing your fluorescent bulbs, than magnetic induction grow
lights may be the right choice for you.
Learn more about induction lighting for growing marijuana!
I hope that helps you as much as it would have helped me when I first
looked into grow lights!
If you haven't started growing marijuana yet, today is the day!
Our one-of-a-kind 2-page Stealth Growers Cheat Sheet will teach you
everything you need to know to discretely start growing a few pounds of
marijuana a year, out of a spare closet.
Click here to learn how to grow weed and download your cheatClick here to learn how to grow weed and download your cheatClick here to learn how to grow weed and download your cheatClick here to learn how to grow weed and download your cheat
If you run into any problems while you're growing marijuanarun into any problems while you're growing marijuanarun into any problems while you're growing marijuanarun into any problems while you're growing marijuana, you
don't have to figure everything out alone. Use our handy marijuana
FOR SERIOUS GROWERS ONLYFOR SERIOUS GROWERS ONLYFOR SERIOUS GROWERS ONLYFOR SERIOUS GROWERS ONLY You've told me you're looking for a complete guide to growing marijuana thatcovers everything, from beginner to ultra-advanced. And picking the right grow lights is just one technique to getting seriously killerharvests. If you want to learn ALL the secrets... Learn from the best! Invest in the most advanced Grow Bible Available: Invest in the most advanced Grow Bible Available: Invest in the most advanced Grow Bible Available: Invest in the most advanced Grow Bible Available: Growing Elite Marijuana + 6bonuses (including one-of-a-kind comprehensive strain guide) Total care explained step-by-step... indoors... outdoors... Monster cropping... advanced growth control... bud production secrets... andmuch, much more... Over 700 pages of pictures, tutorials and advanced insider tips!Over 700 pages of pictures, tutorials and advanced insider tips!Over 700 pages of pictures, tutorials and advanced insider tips!Over 700 pages of pictures, tutorials and advanced insider tips! Get Instant AccessInstant AccessInstant AccessInstant Access to It All Right Here: GrowWeedEasy.com/growing-elite-marijuana I thought I already knew it all, but after I went through this grow bible, Idiscovered that there were still lots of easy ways I could increase my yields andgrow even more potent buds! I find myself going back to it again and again fornew ideas. -Nebula
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Happy growing!
TagsTagsTagsTags CFL Grow Lights General Cannabis Care How-to GuidesMagnetic Induction Grow Lights T5 Grow Lights HPS Grow LIghts TutorialsLED Grow Lights Metal Halide Grow Lights Lights Yields
What to expect: What to expect: What to expect: What to expect: 1 ounce/plant (if you don't run into
problems), up to about 8 ounces/plant.
Recomended for: Recomended for: Recomended for: Recomended for: People who need a few ounces of
weed a month and want a super cheap, super easy,
"low-maintenance" grow style.
Don't be fooled just because it's easy. Even
though I was a complete beginnercomplete beginnercomplete beginnercomplete beginner when I
started, I ended up getting 6.2 ounces6.2 ounces6.2 ounces6.2 ounces of
dried buds off my very first cannabisoff my very first cannabisoff my very first cannabisoff my very first cannabis
plantplantplantplant from my very first grow, which I grew using this system! (Pics
below)
It helps to use a high-yielding strain (Northern Lights is great because it's
high-yielding, tends to grows short, and is low odor).
I still grow this way today in a spare cupboard and I get an average of get an average of get an average of get an average of
8-14 ounces of dried buds off each plant8-14 ounces of dried buds off each plant8-14 ounces of dried buds off each plant8-14 ounces of dried buds off each plant, though I use advanced
growth control techniques to take advantage of the great light that CFLs
produce within 2-8" of the bulb.
These results are not typical for your first try unless you've put in a lot of
extra research and really watch and tend to your plants throughout your
grow. Which brings me to my next point..
This method is not for everyone!This method is not for everyone!This method is not for everyone!This method is not for everyone!
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That's because growing weed with CFLs isn't the highest yielding method.
It's not suitable for a large grow, and it's not going to work if you aren't
willing to watch over your plants.
But it's super cheapsuper cheapsuper cheapsuper cheap, super easysuper easysuper easysuper easy, and if you just need a few ounces ofjust need a few ounces ofjust need a few ounces ofjust need a few ounces of
dried budsdried budsdried budsdried buds a month, it's the perfect "low-maintenance" way to growperfect "low-maintenance" way to growperfect "low-maintenance" way to growperfect "low-maintenance" way to grow
weedweedweedweed.
I think it would be safe to assume that even a beginner can expect to get
1-4 ounces of dried buds if you just follow these instructions. Even if you
mess up (and you will), you'll still get at least that if you can get your
plants to harvest.
Here's a pic of my very first grow using this method! Here's a pic of my very first grow using this method! Here's a pic of my very first grow using this method! Here's a pic of my very first grow using this method!
You will be growing your marijuana plants indoors in a soil-less medium
called Coconut Coir (often called coco coir, or even just coir). Coco coir is
a natural fiber made from the husk of coconuts that naturally stimulates
the roots of plants and is forgiving when growing marijuana.
For feeding (water plus nutrients), you will hand-water them whenever
your plants get dry and you will provide them with all the nutrients they
need right in their water.
For lights, all you need are some cheap CFLs (Compact
Florescent Lights) like the ones you get from your local
hardware store.
These common bulbs are much more efficient than old
fashioned light bulbs (which can't be used to grow
plants) and CFLs don't use much electricity or produce as much heat
compared to some other grow lights.
For a stealth marijuana grow inside a tinyl space, nothing can beat CFLs as
marijuana grow lights.
Because CFLs have a short light range (8 inch max) theis tutorial works
best for growing plants that are kept shorter than 3-4 feetgrowing plants that are kept shorter than 3-4 feetgrowing plants that are kept shorter than 3-4 feetgrowing plants that are kept shorter than 3-4 feet. You want
to focus on training your plants to grow wide instead of tall.
That means you will choose either...
A compact grow when you keep your marijuana plants small and
harvest often OR
A controlled grow where you allow your plants to get bigger / wider,
but you maximize the CFL light range by training your marijuana
plants to grow short and bushy
You can still get at least a couple of ounces off each plant, even when
plants are kept short and you will be able to harvest your crop in only 3-4
months.
This system reduces many of the problems associated with an indoor soil
grow, and is also much easier than almost any other hydroponic style
grow.
It is a great way to learn about how marijuana plants grow and after doing
one harvest yourself, I guarantee that you will start getting millions of
ideas on how you want to do your next grow.
Pros of Growing Marijuana with CFL Grow LIghts and Coco CoirPros of Growing Marijuana with CFL Grow LIghts and Coco CoirPros of Growing Marijuana with CFL Grow LIghts and Coco CoirPros of Growing Marijuana with CFL Grow LIghts and Coco Coir
Cheap and easy to start
Cheap and easy to maintain even for a complete beginner
Forgiving way to learn how to grow weed
Perfect for growing 1-2 plants
Will produce a smokable harvest in 3-4 months
Get 1-8 ounces/plant (harvest yields depend mostly on two things:
how big you grow your plant and the light intensity you provide to
the buds during the flowering stage)
High quality bud since the plant is fed hydroponically
Best method for a very small grow space
Can be used with any strain of marijuana, whether it was started
with seeds or clones
ConsConsConsCons of Growing Marijuana with CFL Grow LIghts and Coco Coir of Growing Marijuana with CFL Grow LIghts and Coco Coir of Growing Marijuana with CFL Grow LIghts and Coco Coir of Growing Marijuana with CFL Grow LIghts and Coco Coir
CFL grow lights are not cost effective when growing more thannot cost effective when growing more thannot cost effective when growing more thannot cost effective when growing more than
1-2 flowering marijuana plants1-2 flowering marijuana plants1-2 flowering marijuana plants1-2 flowering marijuana plants at a time, if you're growing more
than a handful of plants, you'll probably want to invest in a LED Grow
Light or an even brighter marijuana grow light to supplement your
light intensity, instead of just trying to add more CFLs.
Hand-watering plants is simple, but can be a pain if you have a lot
of plants OR very small pots (which need to be watered more often)
You have to adjust your CFL bulbs 1-2 times a week, as your plants
will be rapidly growing into them
For best results and to be able to harvest several ounces/plant with
this method, you will need invest your time to learn how to keep
your marijuana plant short with basic marijuana growth control
This is really a perfect way to grow your first harvest if you "just want to
get your feet wet" because it's so forgiving and you will really learn an
incredible amount about growing by using this method.
I used this technique for my first grow, and even though I made a lot of
mistakes, my plants produced great buds.
.
What you will need
Marijuana Marijuana Marijuana Marijuana SeedsSeedsSeedsSeeds or or or or ClonesClonesClonesClones
High-quality hydroponic nutrientsHigh-quality hydroponic nutrientsHigh-quality hydroponic nutrientsHigh-quality hydroponic nutrients which are designed for
marijuana. I recommend Fox Farms Hydroponic Liquid Nutrient trio
since that's what I exclusively used with good results on my first
grow. Another good choice is Canna Coco Nutrient A & B which is a
two part system made specifically for coco coir. You can usually find
these brands of nutrients at any hydroponic store which is usually
going to be cheaper than purchasing online if you count the price of
shipping.
PotsPotsPotsPots to plant your marijuana in. I recommend getting pots that are
2-3 gallons each. Only get 5 gallon pots if you need to be able to go
a long time without watering or if you want to grow tall plants.
Coco coirCoco coirCoco coirCoco coir (and perliteperliteperliteperlite if you'd like) which can be purchased online
or at a hydroponic garden store, Sometimes you can find a soilless
mix that already has both coco coir and perlite in it.
CFLs (Compact Florescent Lights)CFLs (Compact Florescent Lights)CFLs (Compact Florescent Lights)CFLs (Compact Florescent Lights). You will need about two
40w(150w incandescent equivalent) CFLs per plant to start. These
lights are easily found at the store or online. You can get different
wattage bulbs, but I like bulbs close to the 40w range because they
are a small, manageable size but still produce a lot of light. By the
time your cannabis is flowering, you may need to get more bulbs to
fill in any 'shadowed areas' up to maybe two or three more lights per
plant. It's optimal to use 'daylight' (6500k) colored bulbs for the
vegetative stage and 'soft white' (2500k) colored bulbs for flowering
(though you can use either kind during either stage and your plant
will come out fine). I like to use a mix to make sure my plants get a
Enough light sockets for all your lightbulbsEnough light sockets for all your lightbulbsEnough light sockets for all your lightbulbsEnough light sockets for all your lightbulbs (they're less than $5
apiece at my hardware store, usually they also come with some sort
of clip you can use to clip your lights anywhere. You can double-up
light bulbs to a socket (more info below) so that you have less total
sockets you have to deal with.
A timerA timerA timerA timer to make your lights go on and off when you want. You can
get a cheap one for $5 or spend up to $30 getting a nice digital one
You don't necessarily need one to start if you veg your plants in light
24 hours a day, but you will need to get a timer by the time you
start flowering your plant (about a month in) unless you want to turn
the lights on and off manually every day. You can buy timers at your
hardware store or online.
pH Control KitpH Control KitpH Control KitpH Control Kit: : : : This contains pH Up and pH Down (to adjust pH of
your water) and a simple strip test. Another option for testing pH is
a fancy (and more expensive) digital pH tester though my plants did
just fine with the strip test that comes in the much cheaper pH
Control Kit. All hydroponic stores and some gardening stores with
sell pH Control Kids. You will want to adjust your water so it's
around 5.5-6.0 pH when you water your plants. How do I check and
adjust the pH of my water?
Estimated Total Cost for Growing Five PlantsEstimated Total Cost for Growing Five PlantsEstimated Total Cost for Growing Five PlantsEstimated Total Cost for Growing Five Plants
Marijuana Seeds or Clones: Free - $10/plant
Nutrients: Fox Farms Hydroponic Nutrient Trio (quart) or Canna Coco
Nutrient A & B (1 Liter) - $25-$45
Coco Coir - $25 / big bag
Perlite (optional) - $10 / bag
Five 2-gallon pots - $1 - $5 each x 5
Four 40w CFLs per plant - $7 - $10 each CFL, or $28 - $40 per
plant x 5
Four light sockets per plant at $4 - $7 each or $16 - $28 per plant
x 5
Power timer $5 - $30
pH Kit - $10 - $30
Total: Total: Total: Total: $290 - $555 in total start-up costs
Ten ounces of bud retail value: Ten ounces of bud retail value: Ten ounces of bud retail value: Ten ounces of bud retail value: You may get even more but a
reasonable estimate is a total harvest of two ounces of dried bud from
each of the five plants. At $30-$70/ eighth, ten ounces is equal to $2400
- $5600 which is worth 5-10 times the money you need to put in to get
started. I got a total 6.2 ounces6.2 ounces6.2 ounces6.2 ounces of dried buds off my first cannabis plant I
grew using this system (pictured below in flowering section). I still use
this method today and on average I get 3-4 ounces off each cannabis
plant.
After your first grow, you will only need to get more plants, more coco
coir, and more nutrients which will significantly bring down the start-up
Remember, you can start out with fewer lights and light sockets(start with
2-3 per plant), and will only need to get more as you notice shadowy
patches on your plants that aren't getting enough light. The great thing
about all of the items needed for this technique is they can all be used in
future grows, even if you decide not to continue with this method. For
example, even if you end up getting HID lights eventually, you will always
be able to use the CFLs for starting out new plants, or for adding
additional side lights.
A Note about Using CFL Lights
You need about two You need about two You need about two You need about two 42w(150w incandescent equivalent) CFLs42w(150w incandescent equivalent) CFLs42w(150w incandescent equivalent) CFLs42w(150w incandescent equivalent) CFLs per per per per
plant to start.plant to start.plant to start.plant to start.
These lights are easily found at the store or online. You can get lower or
higher wattage bulbs, but I like bulbs close to the 40w range because
they produce a lot of light, but are still a small, manageable size.
By the time the plants are flowering, you may need to get more lights per
each plant to fill in any 'shadowed areas' up to maybe two or three more
lights per plant.
It's optimal to use 'daylight' (6500k) colored bulbs for the vegetative stage
and 'soft white' (2500k) colored bulbs for flowering (though you can use
either kind during either stage and your plant will come out fine).
I like to use a mix to make sure my plants get a full spectrum of light.
I recommend getting some heavy duty clamp light sockets which you can
use to power your light bulbs. These light sockets are able to clamp to
most anything and they come with a reflector for your lights.
When looking for clamp light socketsWhen looking for clamp light socketsWhen looking for clamp light socketsWhen looking for clamp light sockets, avoid anything that's made of
plastic (it's cheap and will break) and try to find something with at least a
9 foot long cord. You'd be surprised at how annoying it is to try to find a
way to make a 6 foot cord work.
To maximize the light your plants are getting, you can use a light socket
extender and a twin light socket adapter to fit two lights per each clamp
light socket (without the extender, they probably won't fit).
Setting up two lights per socket can often be cheaper than buying an
individual light socket for each light, especially if you buy online. It also is
really convenient for arranging around your plant.
Click here to learn more about grow lights and the length of time you provide light to
your cannabis plants each day.
How to get started
Optionally fill the first couple inches of your pots
with perlite for extra drainage, and then fill the rest
of the pot with coco coir.
Water your pot with coco coir thoroughly until water
drains out the bottom before adding your seeds or
clones.
Set up your lights so that they can start around the height of your pots
and eventually be raised to the final height of your plant (2-3 feet
depending on your marijuana strain and how long you let you plants stay
in the vegetative stage).
Once you have everything set up as described, simply add your marijuana
seeds or clones and set up your lights so that they're about 4 inches away
to start.
Watering Schedule
You will want to start feeding your plants with
nutrients at quarter strength for the first week, then
work your way up to full strength slowly.
I recommend following the instructions exactly as
provided by the nutrients.
For example, if you are using Fox Farms Hydroponic
Liquid Nutrient trio, just follow the feeding chart that comes with the
bottles and water your plant with nutrients every other watering.every other watering.every other watering.every other watering.
When not using nutrients, make sure you still pH your plain water before
your feed your marijuana!
This is important! This is important! This is important! This is important! Water your marijuana plants until you get at least 20% 20% 20% 20%
extra runoff water extra runoff water extra runoff water extra runoff water out the bottom.
Then don't water your marijuana plants again until the top of theThen don't water your marijuana plants again until the top of theThen don't water your marijuana plants again until the top of theThen don't water your marijuana plants again until the top of the
This will start out with you watering the plants every couple of days, and
may end up with you watering them once a day towards the end of the
marijuana flowering cycle.
This bears repeating, you want to ensure that you have about 20-30%
extra run-off water come out the bottom of the container every time you
water your plants.
The reason for this is that coco coir tends to form natural salts if it the
fertilizers just sit in there and never get washed out. Making sure you
keep adding water until you get run-off is also a great way to make sure
that your plants are draining properly.
As I said before, make sure to feed your marijuana plant with plain, pH'ed
water every other watering.
This will greatly help reduce the amount of salt buildup and prevent
nutrition problems from occuring. If your marijuana shows signs of
droopingdroopingdroopingdrooping, chances are you are over or under-watering.
In order to prevent over or under-watering, make sure you watermake sure you watermake sure you watermake sure you water
thoroughly every time, and wait to water again until the top inch ofthoroughly every time, and wait to water again until the top inch ofthoroughly every time, and wait to water again until the top inch ofthoroughly every time, and wait to water again until the top inch of
If you don't change your schedule to 12-12, chances are your marijuana
will just keep growing forever and never make buds.
After switching to 12-12, you should start noticing your plant making it's
first sex organs after a week or two. Females will grow white hairs and
males will start growing grape-like balls.
In order to maximize on the amount of bud you get, you will want to
make sure you remove any males so they don't impregnate you females.
If they stay together than your females will get pollinated by the males
and will end up making lots of seeds instead of buds.
Unless you have a reason to keep males (for example breeding), you
probably want to just kill any male plants because they won't make any
usable bud anyway.
When growing with CFLs, it becomes harder and harder to fully illuminate
the plants as they get bigger and grow more branches. You will maximize
the total amount of buds you get by keeping the plant smaller (and
therefore easy to bathe in light), and then harvesting more often since
your plants will be ready to harvest much sooner.
As the plants get taller and starte blooming, you may need to get a couple
more CFLs to light them from the sides. Basically if you see any dark or
shadowy areas that are more than 6 inches from a CFL, then you should
get another CFL to plug in that 'hole.'
Towards the end of the flowering cycle as your marijuana approaches
harvest time, you may notice that some of the oldest leaves startoldest leaves startoldest leaves startoldest leaves start
turning yellow and falling offturning yellow and falling offturning yellow and falling offturning yellow and falling off. This is totally normaltotally normaltotally normaltotally normal and is a sign that
your plant is taking nitrogen out of the leaves and putting them into the
buds/flowers.
You will want to stop feeding your marijuana any nutrients for the last two
weeks before harvest to ensure the best tasting bud. Simply feed them
plenty of water without nutrients for these last two weeks, but make sure
you're still adjusting the pH so they absorb any leftover nutrients in the
coco coir.
I usually stop feeding my cannabis nutrients and start feeding them water
when about 75% of all the pistols (hairs) have turned dark and started
curling in towards the buds.
Harvesting
Pleast view the Harvest Section of my general
cannabis grow guide for more information about
when and how to harvest your plant. This guide
should tell you exactly what to look for as far as
determining if your cannabis is ready for harvest.
In the past, we’ve covered how to grow train your plants to grow
short and how you can maximize your space when choosing an
auto-flowering or photoperiod strain, I’d like to share some tips for
growing with the cheapest marijuana grow lights that fit in extremely
small spaces... CFLs!
What are CFLs?What are CFLs?What are CFLs?What are CFLs?
CFL stands for "compact fluorescent light" and even though these lights
can be found at any hardware or grocery store, they actually give off a
really great light spectrum for growing marijuana.
Never get CFLs confused with old-fashioned incandescent light bulbs...
Benefits of growing with CFLsBenefits of growing with CFLsBenefits of growing with CFLsBenefits of growing with CFLs
Cheap
Low heat
Low electricity
Stealthy
CFLs are easy to find in grocery and home improvement stores
Suited to very small grow spaces
CFLs are a great option if you...CFLs are a great option if you...CFLs are a great option if you...CFLs are a great option if you...
Must grow in a very small space (computer case, cupboard, or
tiny closet)
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Growing Weed With CFLs - What Growers Need to Know | Grow... http://growweedeasy.com/growing-marijuana-with-cfls
1 of 8 8/13/2013 12:25 AM
Plan to grow 1-2 plants
Want to harvest a few ounces of buds
Are willing to check on your plants at least once every few days
(you will need to adjust the CFL grow lights relatively often
since they’re kept very close to plants)
CFLs are CFLs are CFLs are CFLs are not not not not well suited for growers who want this...well suited for growers who want this...well suited for growers who want this...well suited for growers who want this...
Lots of plants
Pounds of buds per plant
Large grow tent
Refuse to learn [how to train plants]
Can’t tend plants regularly
“Baby Pic”
Here's a picture of one of my very first grow with CFLs.
-Nebula
How Many CFLs Do You Need To Grow Marijuana?How Many CFLs Do You Need To Grow Marijuana?How Many CFLs Do You Need To Grow Marijuana?How Many CFLs Do You Need To Grow Marijuana?
There are lots of formulas that growers can use to determine how many
CFLs they will need.
For example, some growers recommend that you go by the amount of
lumens (light) produced, or by the total wattage of your lights.
However, I think a simpler approach is much more effective, and will
result in better yields for you.
Simply follow these principles with CFLs to get great yields every time:
All parts of the plant should be within 8-10” of a CFL bulb (CFLs
should be kept 2” away from the tops of your plants
Any “shadowy” areas need another bulb
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2 of 8 8/13/2013 12:25 AM
More bulbs = better results (You want to surround your plant
with as many bulbs as possible because the penetration of CFLs
is poor; in other words, more small CFLs is more effective than
a few big CFLs)
Real-life Example: 7 x 26W CFLs (at 182 watts total) that are
spread in an array around the plant will be more effective for
growth than 1 x 200W CFL, even though they use less total
electricity.
More lumens = better results (you can’t really give your plant
too much light when growing with CFLs, more is better)
In the flowering stage, make sure that buds get direct access to
intense light & keep CFLs as close to buds as possible without
burning them (this will dramatically increase yields with CFLs)
The size and shape of your plant is going to have the biggest effect on
how many CFLs you’ll need, and that’s why no “formula” is going to be
accurate all the time. Any formula is just a rough estimate.
What if I’m still not sure how many CFLs to get?
You can use this formula to get started with planning your grow space,
though I recommend using the guidelines above once your plant has
actually started growing.
4,000+ lumens/sq foot4,000+ lumens/sq foot4,000+ lumens/sq foot4,000+ lumens/sq foot (more is even better) - lumens is the measure
of light as perceived by the human eye, and this number will be listed on
the CFL bulb packaging
Example of Estimating Number of CFLs Needed For Your Grow Space:
Multiple width x length of your grow space to determine theMultiple width x length of your grow space to determine theMultiple width x length of your grow space to determine theMultiple width x length of your grow space to determine the
sq feet.sq feet.sq feet.sq feet.
Let’s say your grow space is 2’ x 2’ = 4 sq feet
1.
Multiple the sq feet of your space by 4,000 lumens toMultiple the sq feet of your space by 4,000 lumens toMultiple the sq feet of your space by 4,000 lumens toMultiple the sq feet of your space by 4,000 lumens to
determine the total lumens needed for this space.determine the total lumens needed for this space.determine the total lumens needed for this space.determine the total lumens needed for this space.
So 4 sq feet x 4,000 lumens/sq feet = 16,000 total lumens for
that space
2.
Divide this number by the lumens produced by each bulbDivide this number by the lumens produced by each bulbDivide this number by the lumens produced by each bulbDivide this number by the lumens produced by each bulb
If you’re getting 42W CFLs which are rated at 2,650 lumens
apiece, that would be 16,000/2,650 = ~6
3.
This number is the minimum number of CFLs needed for yourThis number is the minimum number of CFLs needed for yourThis number is the minimum number of CFLs needed for yourThis number is the minimum number of CFLs needed for your
spacespacespacespace
That means in this case you’d start with 6 (or more) 42W CFLs
4.
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3 of 8 8/13/2013 12:25 AM
Remember, this formula is just an estimate, and you will get the best
results if you also follow the guidelines listed above.
Tip for maximizing the light to your plants: Use the power of reflection to
minimize light loss. Cover your walls with reflective mylar or paint them
with flat white paint. Utilize reflectors to aim more light where you want.
What Color CFLs Should I Get? (CFLs and Light Spectrum)What Color CFLs Should I Get? (CFLs and Light Spectrum)What Color CFLs Should I Get? (CFLs and Light Spectrum)What Color CFLs Should I Get? (CFLs and Light Spectrum)
When you’re buying CFLs, they come in different “colors.” Some are more
orange/yellow, some are almost blue, and others almost look like
daylight.
The truth is that all CFLs will work for growing, but some are better than
others....
6500k colored bulbs6500k colored bulbs6500k colored bulbs6500k colored bulbs (Cool White or Bright White)
Best suited to Vegetative Stage
By using the 6500k colored bulbs during the vegetative stage, you’ll be
giving your plants more blue light, which helps plants grow short and
I want to see a real CFL grow in action! Show me a CFL dresser microgrow
with lots of pictures: http://growweedeasy.com/entire-microgrow-
pictures-week-by-week
I'm definitely choosing CFLs... if you know you’re ready to get started
growing with CFLs, click here to view my step-by-step tutorial on growing
weed with CFLs in coco: http://growweedeasy.com/easiest-
grow-method-cfl-coco-coir
I'm thinking about choosing HPS grow lights instead... Help me pick out
the right lights and teach me how to set them
up: http://growweedeasy.com/hps-grow-lights-setup
Start Growing with CFLs Today!
These CFLs are proven for growing marijuana. They also make great
supplemental lighting.
26W CFLs
Vegetative CFL - 6500k
Flowering CFL - 2700k
42W CFLs
Vegetative CFL - 6500k
Flowering CFL - 2700k
65W CFLs
Vegetative CFL - 6500k
Flowering CFL - 2700k
Don’t forget to get a light socket (and possibly a splitter) for each
CFL bulb!
Reflect your light for max efficiency
Cover walls in mylar or flat white paint
Use reflectors (or make your own like WasabiMayo does below!)
To all you growers on a budget: It's possible!To all you growers on a budget: It's possible!To all you growers on a budget: It's possible!To all you growers on a budget: It's possible!
Growing Weed With CFLs - What Growers Need to Know | Grow... http://growweedeasy.com/growing-marijuana-with-cfls
6 of 8 8/13/2013 12:25 AM
by WasabiMayo
Check out WasabiMayo's amazing (and budget) CFL microgrow in
pIctures...
View full album with a write-up by WasabiMayo right here:
Growing Weed With CFLs - What Growers Need to Know | Grow... http://growweedeasy.com/growing-marijuana-with-cfls
8 of 8 8/13/2013 12:25 AM
Selective Light Training (SLT)
Light Spectrum And Selective Light TrainingLight Spectrum And Selective Light TrainingLight Spectrum And Selective Light TrainingLight Spectrum And Selective Light Training
by SuperAngryGuy
Published with permission.
Note by Nebula:
I came across this incredibly interesting article by
SuperAngryGuy, an avid grower who has been
doing some interesting research into marijuana
grow lights and who is kind enough to allow others
to repost his work so that the growing community
can benefit from his research.
This technique is NOT aimed at the beginner
grower, and is aimed at the intermediate to
advanced grower who is interested in learning the cutting edge technology of
growing and loves getting down and dirty with a little experimentation.
If any of you have been using SLT to alter the way your plants grow, I'd love to
hear from you!
-Nebula
What is Selective Light Training?
Selective Light Training is about hitting certain parts of a plant with light for the
purpose of protein manipulation.
I have yet to run across a LED manufacturer/reseller who has a clue about light
sensitive plant proteins.
A typical plant will have in excess of 1,000. The phot1 and
phot2 Phototropin proteins are what's being manipulated with blue light.
Blue causes plant cells to not elongate (as much) so hitting the stem with blue
gives a more compact plant.
How to Use SLT To Your Benefit
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1 of 7 8/13/2013 12:17 AM
For use on stems, as shown in this young Jack
Herer Plant (pictured to right), you have to get
the blue LED array up close to the stem
with uninterrupted light.
That is why I use 20x55 degree oval LEDs. 20
degrees side to side allows a little aiming slop and the 55 degrees vertical insure
light overlap.
The LEDs can be found here. Use model number 725LB7C. These are cheap
Chinese LEDs so you need to under drive them to around 10 milliamps.
Putting 3 in series with a 330 ohm resistor and building an linear array allows one
to use an unregulated, 12 volt power supply.
All of this is to keep costs down (those LEDs are about 3
cents each out of China in quantity). I've never seen one
of these blue LEDs burn out at the lower power level.
To the left is a close up of how the light sticks look and
below that is an even closer showing the epoxy
encapsulation.
These light sticks are simple to build (for personal use
only....legal of course), and you should be able to see
what you need to do with the pics.
With blue light blasting the stem only, other wavelengths of light can be used
on the different parts of the plant.
In my experiments with sweet basil, I've used blue on the stem and amber on the
leaves.
The resulting leaves are 4 times larger than normal.
Not all plants react the same way, and results do seem to be strain specific
(sweet basil, lettuce leaf basil and purple basil react differently).
To the right is a mystery skunk marijuana plant giving to me
where I can get 4-5 internodes per inch, even at lower main
lighting levels.
Excess stem elongation is a thing of the past and you will get
significantly more growth per area or volume.
For short day plants, use the light sticks for veg growth and the
first two weeks of flowering only.
Pictured below are two examples of using the light sticks with intracanopy
lighting.
Notice how there are different light sticks with different light colors being
directed to specific parts of the plant.
Submit
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Notice the fan.
Next to the young plant, you can see what
an older plant looks like with about 3
weeks to go, also using intracanopy
lighting.
I'm expecting +3 ounces per square foot+3 ounces per square foot+3 ounces per square foot+3 ounces per square foot equivalent (this is 2/3rds of a
square foot) with this plant but while also using intracanopy lighting.
Next is Purple ArrowPurple ArrowPurple ArrowPurple Arrow (pictured to right) that had
selective lighting training (it's a low yielding strain).
This plant has not been topped and shows how different
strains can give morphological differences.
The blue light on the stem tends to produce plants that
are not as wide but you have to test the strain to see
how well SLT works for that strain.
This allows more plants per area and more yield with intracanopy lighting.
Intracanopy lighting often requires foliar nitrogen spraying and will
produce a higher thermal load in your grow area as well as more humidity
from the increased photosynthesis.
You can not just use blue side lighting to pull this off.
The leaves tend to grow downwards with blue side
lighting blocking light from hitting the stem.
You must get the blue light in close to the stem which
is the difference between side lighting or intracanopy
lighting and selective light training.
I'll be adding to my lighting guide soon a primer on LEDs and how to build your
own intracanopy apparatuses.
Also, I should point out that the blue LEDs only need to be used on the only need to be used on the only need to be used on the only need to be used on the
growing parts of a plant growing parts of a plant growing parts of a plant growing parts of a plant (zone of division and zone of elongation).
I've tested this with hardwoods, like Fuji Apple on
a P-22 rootstock, and it does work for making
more compact grafts as long as you hit the
growing part of a hardwood before the bark has
formed.
I'm still waiting to try this on coffee tree saplings to try to make a more
compact and economically efficient coffee tree.
A Quick Note About Light SpectrumA Quick Note About Light SpectrumA Quick Note About Light SpectrumA Quick Note About Light Spectrum
Here is a spectral absorption profile of a
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3 of 7 8/13/2013 12:17 AM
high nitrogen marijuana leaf (Jack Herer).
You can see that about 90% of the green
light is being absorbed (it's on a 18%
reflective gray card).
Plants can use green light and at higher
lighting levels green is more
photosynthetically efficient than red.
This is because the top layer of chloroplasts that contains chlorophyll
becomes saturated while green can penetrate deeper in to leaf tissue
(sieve effect) and reflected around until absorbed by another chloroplast
containing chlorophyll (detour effect).
This efficiency can be measure through chlorophyll fluorescence. Green
light used alone tends to cause a lot of elongation. HPS grow lights have
give off a lot of green/yellow/amber light.
We can use a green LED "safe light" because the two main protein groups
responsible for photoperiodism regulation, the crytochrome and
phytochrome proteins, are largely green light insensitive. This has nothing
to do with photosynthesis. There are many more proteins involved with
photoperiodism and flowering.
Using a Cheap Lux Meter as a Plant Light Meter
We use a light meter to measure light intensity. Light intensity plays a very
important role in photosynthesis rates. Photosynthesis rate is the major
determination in our yields.
To a point, more light = more yield.
A light meter only determines how much light there is, not the spectrum.
I showed some spectrum shots below only to illustrate a point of how our eyes
and a lux meter perceives light and versus what's closer to what a plant sees.
For everything but LED grow lights, this is close to the readings that we want with
a cheap lux light meter as measured at the top of the plant canopy level:
15000-20000 lux____ the lower end of what we want for veg growth
35000-40000 lux____ what we want to try to hit for flowering
75000 or so lux_____ it's pointless to go beyond this level of light intensity,
saturation level
We use this information to determine how far away we want the light source from
the plant. It's not the case that we should just try to get the plant as close to the
light without burning. There are too many types of lights to use that as a rule of
thumb as well as too many other variables.
For example, blowing air on the light and plant will allow us to get the plant closer
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4 of 7 8/13/2013 12:17 AM
to a light without burning but we in the process could go above the 75000 lux
point.
That's just a waste of energy since we're now saturating the plant.
For best yields per lighting levels, go with the 35000-40000 lux level.
Just accept that or read below on light intensity theory.
This information is not used to determine the type of light we use.
For example, we generally want redder lights, which have a lower color
temperature, for flowering and bluer light, which have a higher color temperature,
for vegetative growth. If you want the theory why, read
the photomorphogenesis sections of the lighting guide.
When using a light meter, it is typically best to use it with the sensor/meter
pointing straight up rather than directly at the light source. That little white
semi-sphere or flat piece of plastic you see with the light meter compensates for
this.
What you should take away from this is that a lux meter is accurate
enough to give meaningful measurements with white lighting.
-------you do not need to read beyond this point, the rest is a lot of
theory-------
Here's the conversion charts for using a lux meter as a quantum light meter.
Thank you jcraw69 for pointing this link out to me!
Instead of asking how much light do I need, spend $20-30 on an Ebay lux
meter and get a good reading. If you use CFLs without reflectors, for example,
you'll need twice as many of them.
If in doubt use 75 as a conversion number which is close enough. This means for
veg growth with a white light source (more on this below) you want to be around
at least 15000-20000 lux (about 200-250uMol), for flowering you want to try to hit
35000-40000 lux (about 500uMol) and the do not go over line for flowering is
right around 75000 lux (about 1000uMol which is the photosynthesis saturation
point).
Do not use a cheap analog lux meter. I've tested one type and they were way off.
I haven't tested cheap digital lux meters but I'm pretty sure most are going to be
close enough (the analog ones had impedance matching problems with the
analog scale so were giving bad readings in brighter light).
You still can not use a lux meter with LED grow
lights but can with white LEDs. The conversion
factor is just way too far off.
For example, as measured with my own
spectrometer, a red 647nm LED was at a 10.3
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conversion factor and a red 620nm LED at 44.
A blue 462nm LED measured in at 12.8.
When comparing two different light sources in a grow comparison, they must be
done at the same lighting intensity.
Why?
First, photosynthesis isn't linear except between about 50-500 or so uMol and as
you can see in the above paragraph, LEDs commonly used in grow lights give
wildly different readings than white lights like HPS.
Second , many plant proteins are expressed at different lighting intensities which
can and will affect plant development.
Third, chloroplasts can move to the side walls at higher intensities of blue light
lowering plant photosynthesis efficiency. This is called cytoplasmic streaming and
is done as a form of photoprotection.
An example can be seen here in this sped up 4 second video.
Here's a few examples of light as measured in power by spectrum and how our
eyes and a lux meter would perceive it. Here's a 2700K CFL as a true
spectrum and how a lux meter reads it.
Notice how much the red/green (the middle and right spike) ratio changes.
This is because our eyes and lux meters are much more green sensitive.
Why are quantum light meters so damn expensive? Economy of scale and
higher accuracy. The cheapest quantum light meter that can give true
measurements with LED lighting is $800.
So, I've argued in the past that lux meters were next to worthless as plant light
meters. I was wrong on this point for white light and didn't realize it until about 10
days ago when I got a spectrometer.
Thank you SuperAngryGuy For Your Constant Contribution to the
Forefront of Growing Science
Read his incredible guide on marijuana lighting. Or check out his wiki page.