2
College of
Agriculture and Natural Resources
What is organic gardening?
• No synthetic pesticides or fertilizers – Only Organic Materials Review Institute
(OMRI) approved?
– https://www.omri.org/
• U of MD recommendations for home gardeners are organic
What is sustainable gardening?
• Mimic the natural ecosystem
– Good bugs eat bad bugs
• Use local resources
– Reduce purchased inputs
• Employs knowledge, planning and skill
• Apply NPK according to soil test recommendations
• Apply IPM principles
• Make optimal use of water
MGs teach a common-sense, ecological approach
• Rely on local materials and resources
– Compost neighbors leaves and your grass
– Local animal manure
– HC compost or Leafgro
• Maximize biological and genetic diversity to strengthen your garden eco-system.
– Example: Plant an assortment of annual flowers and herbs to attract and feed beneficial insects.
5
Unbordered raised beds
Ingredients to a Successful,
Organic Vegetable Garden
• Healthy soil • Lots of organic material
• Shooting for % OM in soil test > 4%
• Normal ranges from 1% to 3%
• Proper soil pH 6.2-6.8
• Proper nutrient levels • Soil test
• Follow NPK recommendations
• Secondary and micro nutrients
• Sufficient soil moisture
• Practice Integrated Pest Management (IPM)
Importance Of These Ingredients
• Healthy highly enriched organic soil with
proper moisture level creates healthy plants
which resist insect attack
• IPM • In nature, bad insects are predated by beneficials
• Use physical controls and erect barriers to pests
• Use targeted applications for specific pests
• Use broad spectrum organic insecticides only as a
last resort
What is Healthy Soil
• Soil rich in organic matter with lots of
invertebrates • Has lots of pores for air and water
• Six inches of OM for new gardens
• One inch for established gardens
• % OM of soil s/b > 4%
Healthy Soil (cont.) • Soil with proper pH and nutrient levels
• Do a soil test
• Follow recommendations
• University of MD. recommends .2# of N/100 sq. ft.
• 3-4-3 .2/.03=7 lbs./100 sq. ft.
• Blood meal 12-0-0 .2/.12=1.6 lbs./100 sq. ft.
• HC compost 1.41-0.6-1.36 rich in N
• 1 inch over 100 sq, ft. = 8 cu. ft. = 200 lbs.
• 200 X 0.0141= 2.82 lbs. N
• 15% available = .42 lbs.
Healthy soil (cont.)
• References at www.extension.umd.edu/hgic click on
“Soils” or click on “Information Library”,
“Publications” and “Soil, Mulch and Composting”
• HG11 Soil test basics
• HG110 Selecting and using a soil testing
laboratory
• HG 42 Soil amendments and fertilizers
• FS782 Basics of soil and plant fertility
• http://www.youtube.com/UMDHGIC to see video on
collecting a soil test sample
Soil Moisture
• On average plants require one inch of water a week
• On a 4 by 8 foot bed, that’s 20 gallons of water
• Moisture needs to be delivered to the plant roots
• Most efficient method of delivery is drip irrigation • http://www.youtube.com/UMDHGIC look or search for video on
“Drip Irrigation”
• Can also use soaker hoses
• Mulching plants helps conserve soil moisture – Organic (dried grass, newspaper, compost )
Intensive planting
• Assume a four foot wide bed
– In a 2 or 3 foot long area plant 5 broccoli plants in an x pattern
– Plant 4 lettuce plants between the broccoli plants
B L B
L B L
B L B
Intensive planting (cont.)
• Plant three rows of green beans in 2 X 4 square
– 36 plants lots of beans
• Four rows of beets, carrots or onions
– 48 beets, 48 carrots, 24 onions
• Plant tomatoes three feet apart on the north or west side of the garden
• Plant peppers and eggplants in the same pattern as broccoli above
• Vegetable spacing on Pub HG 16
– Plant Spacing – very important
– Row spacing – less important in raised beds
Succession Planting
• Use transplants when possible
– Cool weather crops (spring and fall)
• Broccoli, cauliflower, lettuce, etc.
– Warm season crops (summer)
• Tomatoes, peppers, eggplants, squash, etc.
• Rotate crops
– Plant beans after broccoli (adds N to soil)
• Inoculate with rhizobium bacteria
– Don’t plant tomatoes, eggplant or potatoes where they have been before.
Cucurbit Tip
• Start 4 inch pot of cucurbits indoors 4/26
– 4 seeds per pot
– Cut off 2 weakest seedlings
• Transplant into garden on frost free date
– 5/17
• Cover with row cover
– Start new pot of seeds when male flowers appear
– Remove row cover when female flowers appear
• Repeat
Start early, end late
• Garden from 4/1 to 12/15
– See Pub. GE 007 or HG 16 for planting times
– Cool season crops (Mid March & April)
• Use low tunnels to extend season forward
– Warm season crops (mid-May & early June)
– Cool season crops (August & September)
• Use low tunnels to extend season
– Garlic (mid-October)
– Winter over spinach and kale for spring crop
Integrated Pest Management
• Simple steps and common sense
• Study
• Spy
• Squish
• An once of prevention is worth a pound of cure
• Companion planting
• A healthy garden with good soil, adequate
moisture and proper nutrition can withstand some
pest predation
Beneficial's v. Pests
• Attract predators and parasites by planting open
faced flowers which attract predators that require
nectar in their adult stage
• Ultimately, predators will increase as prey is
available
• Purchasing predators tends not to be effective
• Build a toad house
• Use broad spectrum insecticides only as a last
resort – they kill beneficals
Common Predators
Praying Mantid
Common Predators
Lady Bird Beetle and Larva
Common Predators Yellow Argiope
Jumping spider
Wolf Spider Orb Weaver
Wheel bug
Common Predators
Common Predators
Syrphid fly and larva: predator of aphids
Common Predators
Parasitized Tomato Hornworm
Common Vegetable Pests Mexican Bean Beetle
Adult Eggs & larvae
• Row cover
• Crush
• Neem, spinosad, Pyrethrum spray top and bottom of leaves
Common Vegetable Pests Cucumber Beetle
Stripped Spotted
Floating row cover
Neem oil, spinosad, Pyrethrum
Common Vegetable Pests Harlequin bug
Adult Eggs & nymphs
• Row cover
• Crush
• Insecticidal soap alone or with pyrethrum or neem for nymphs
• Use cleome as a trap crop
Common Vegetable Pests Flea Beetle
Adults
Floating row cover over hoops
Surround (kaolin clay) – reapply after rain
Neem oil, spinosad, Pyrethrum
Common Vegetable Pests Imported Cabbage Looper
Adult Larvae
• Floating row cover
• Bacillus Thuringensis (BT), insecticidal soap
• Neem oil, spinosad, pyrethrum – use with sticker spreader
Common Vegetable Pests Squash Bug
Adult Eggs & nymphs
• No organic pesticide for adults available to homeowners
• Floating row cover
• Hand pick tear out section of leaf with eggs
• Kill nymphs with neem or hort oil or insecticidal soap
Common Vegetable Pests Squash Vine Bore
Larvae
• Floating row cover
• Cut out borer and mound soil over wound
Common Vegetable Pests Stink Bugs
BMSB Adult Southern Green Stink Bug Brown
• True hard shell bugs like squash and stink bugs are hard to kill
• No organic pesticide available for homeowners to kill adults
• Use row cover where possible or netting
• Hand pick and destroy adults and eggs
• Insecticidal soap and botanicals can be used on 1st and 2nd instars (nymphs)
Targeted Applications for Specific Pests
• With all pesticides
– Always read the label
– Follow label instructions
• Bacillus Thuringiensis
– Cabbage looper and other caterpillars
• Horticultural oils
• Insecticidal soap
Broad Spectrum Killers
• With all pesticides
– Always read the label & follow label instructions
• Pyrethrums
– excites nervous system causing paralysis & death
• Spinosad
– affects the nervous system causing muscles to flex
• Neem oil – azadiractin
– Reduces feeding & acts as growth regulator
• http://npic.orst.edu/
Resources • Grow-It-Eat-It website
– http://www.extension.umd.edu/growit
– Access to valuable and practical gardening tips and information. Share your experiences in our blog
– Click on vegetables, common vegetable problems and vegetable insect pests
• Home and Garden Information Center (HGIC)
– http://www.extension.umd.edu/hgic – Ask the Experts – Send questions and photos 24/7 through this web site for
a quick and thorough answer
• Maryland Master Gardener Program – https://extension.umd.edu/mg
This program was brought to you by
Maryland Master Gardener Program
Howard County
University of Maryland Extension