Site Selection for Strawberries in Mississippi Eric T. Stafne Associate Extension Professor Fruit Crop Specialist Mississippi State University
Site Selection for Strawberries in Mississippi
Eric T. Stafne Associate Extension Professor
Fruit Crop Specialist Mississippi State University
Climate Scales • Macroclimate – large geographic region
• Mesoclimate – local climate
• Microclimate – specific environment around the
plants – Related to plant growth and development post-site
selection decision
Macro Site Selection Considerations
• Length of growing season
• Coolness of the dormant season (chilling)
• Frost
• Frequency of extreme low temperatures
• Summer high temperatures
• Precipitation
Frost • What is the frost-free date?
• How often can it be expected to occur during
growing season?
• Protection of plants
http://strawberries.ces.ncsu.edu/2013/03/what-growers-are-finding-out-this-morning-32213/?src=rss
Summer High Temperatures • Extreme high day and night temperatures in
summer can limit some species
• Fruit quality may suffer as respiration exceeds
photosynthesis
• Flowering inhibited when temps over ~80-85°F
Precipitation
• What is the average annual rainfall?
• When does it normally fall?
• Is drought a common occurrence?
• Is flooding a common occurrence?
Meso Site Selection Considerations
• Elevation • Topography • Slope • Aspect • Prior land use • Soils • Pests and other threats
Elevation
• Can have a big influence on minimum and maximum temperatures in planting area
• Look for “relative” elevation on site and plant near highest point
Low Elevations • More prone to frost
• Less air movement
• Poorer water and air
drainage
• More prone to disease http://ucanr.edu/sites/PAWMBA/Production_Projects/Strawberry/Overview_and_Management_802/
Slope/Aspect • The percent inclination or declination that varies from
horizontal
• Slight to moderate slope is desirable
• Important for cold air and water drainage
• Steep slopes (>15%) not recommended due to difficulty in equipment use and erosion potential
• Aspect is relation to sun, E and S are preferred to N and W
Prior Land Use • Compacted soils
• Prior crops grown on site
– Nematodes – Root rot fungi
• Pesticides used before
http://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/soils/health/biology/?cid=nrcs142p2_053866
Previous Crops • Do not plant in areas previously planted with
alfalfa, raspberries, potatoes, peppers, eggplant, etc. if <4 years ago
• Fumigation may be necessary
• Long-term rotation is best option if feasible
Soil Type • Soil content • Soil pH • Soil moisture • Soil erosion and surface water mgt
http://www.ipm.iastate.edu/ipm/icm/2000/7-24-2000/erosion.html
Soil Content • Strawberries grow in wide range of soil types
• Sandy loam and sandy clay loam preferred
• High clay content or very rocky make bed building
difficult
• Sandy soils require careful irrigation and nutrient management
Soil Characteristics • Ideal soil is well-drained
with adequate water-holding capacity
• Poor soil is poorly drained (internally or externally), and pH is not correct for the crop
http://www.omafra.gov.on.ca/english/crops/facts/frosprot_straw.htm
Soil pH • Favorable root environment • Availability of essential nutrients • Soil pH is key factor • Ideal pH is between 6.0-6.2 • Do a soil test • Low pH one frequent problem • Correct soil deficiencies before planting
Soil pH
http://www.lsuagcenter.com/en/lawn_garden/home_gardening/Understanding+and+Improving+Soil+Fertility.htm
Soil Salinity and Alkalinity • Strawberries have low tolerance for salts
• Highly alkaline soils can cause chlorosis, yield loss
and plant die-back
http://www.fruit.cornell.edu/berrytool/strawberry/leavesandstems/strroundup.htm
Air Movement • The more air drainage, the better
• Air movement provides disease and frost protection
Windbreaks • Wooded area
• Windbreaks on N or NW side of field
• Why?
– Cold protection
http://www.centerforagroforestry.org/practices/wb.php
Water Drainage • Surface drainage is most important; avoid standing
water • Internal drainage is related to soil characteristics • Raised beds compensate for poorly drained soils
http://ucanr.edu/sites/PAWMBA/Production_Projects/Strawberry/Strawberry_Management,_Summary/
Surface Drainage • Permits water to move quickly and completely
• Standing water >1 day will injure plants
Internal Drainage • Avoid poorly drained sites
• Poor drainage can lead to “yellowing” and result in
reduced yields
• Use drainage tiles if necessary
Soil Erosion and Surface Water • Raised beds help with drainage, but not always
enough
• Have enough slope to move water away from field without erosion
• > 2 % slope may lead to excess soil erosion
• Annual ryegrass can reduce erosion
Soil Moisture
• Supplemental Irrigation necessary
http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=3467
Irrigation Water Quality • Test first to determine quality
• Necessary for irrigation and frost protection
• Must have quality and quantity
• Food safety concerns
Strawberry Site Preparation
• Kill existing vegetation
• Apply soil amendments
• Construct beds
• Provide for drainage
Row Orientation • North to South best
– More uniform plant stands – More uniform ripening
• If field is flat, soil drainage most important
Weed Control in Strawberry • Kill perennial weeds
before planting
• Excess fertilization favors weeds
• Keep planted beds free of weeds
Wildlife • Protection from deer critical to success • Other potential pests • Rabbits • Moles • Voles • Coyotes
Crop Rotation • Rotate as often as possible
• Not always practical
• Avoid rotations with crops treated with:
– Herbicides – Plant growth regulators (PGRs)
• Could be carryover
Cover Crops • If rotation not possible, consider summer cover
crops – Reduce soil erosion – Improved soil structure – Improved soil stability and permeability – Decreased crusting – Increased water infiltration
• Incorporate into soil before fall planting
Important Site Components • Windbreaks • Row Orientation • Crop Rotation • Cover Crops • Wildlife • Soil Type • Surface Drainage • Soil Tilth • Internal Drainage • Soil pH • Salinity and Alkalinity • Previous Crops • Irrigation Water Quality • Microclimate
Cultivar Selection for Mississippi Strawberry
Production
Eric T. Stafne Associate Extension Professor
Fruit Crop Specialist Mississippi State University
• Consistent yields • High yields • Good flavor • Pest resistance • Increased shelf life (firmness without sacrificing
flavor and texture) • Aromas
Priorities in Cultivar Selection
Strawberry Cultivar Selection • Select locally adapted cultivars • Cultivars differ in sweetness, preservation quality,
pest resistance and fruiting period. • Plant multiple cultivars to prevent crop loss to
disease and frost events • Find a reliable and experienced nursery • Place your order early
Plant Quality
• Healthy looking
• No disease, insects, nematodes, virus
• True-to-type
• Do not let roots dry out
Plant Types
• Plugs – Most expensive, easier to plant, less
perishable, establish quicker, recommended
• Freshly dug – Highly perishable, hand transplanted
• “Cutoff”
Disease Resistance
• Reduces number of sprays
• Choose cultivars with resistance if possible/practical
• Not all diseases exist in all locations
Botrytis cinerea
• Young blossoms susceptible to Botrytis
• Fruit infections - soft, light brown, enlarge rapidly
Annual vs. Perennial Production
• Growing systems – Annual production on black plastic: plant
in fall, harvest in spring
– Matted row: rejuvenate beds by allowing daughter plants to grow
Plant Spacing • Spacing depends on cultivar and equipment
• Strawberries are planted in 30-inch-wide raised
beds
• Space beds 4 to 5 feet apart
• Space plants 12 to 15 inches in two staggered rows 12 inches apart
Pollination
• Most cultivars are self-fertile • Pollen from other cultivars may
improve fruit set and quality • Insect pollination (primarily bees) is
required
Strawberry Cultivar Selection Bearing types
• June-bearing - Produce a single spring crop
• Everbearing - produce 2 main crops, require long days (12+ hrs of light)
• Day-neutral – insensitive to daylength, but don’t tolerate heat well
June Bearers
• Best for Mississippi • Produce one large crop per year • Have largest berries • Season is 2-3 weeks long • Best yield and quality
Day-Neutral
• Flower and fruit set adequate when temps between 35 and 80 °F.
• In milder growing regions can produce fruit continually throughout year
• Small berry size • Not suitable for Mississippi growing
conditions
Everbearing
• Produce two crops per year • Spring and Fall • Few runners • Smaller crops, especially fall • Fruit quality less
Sweet Charlie
• Early market • Has good quality early, but falls off • Sweet fruit • May be more susceptible to crown rot
Camarosa
• Widely grown around the world • May not yield as much as Chandler • Fruit is large and firm • Plant is vigorous • Susceptible to anthracnose • Harvest at darker color for best quality
FL Production vs. Price 1997-2007
0
10
20
3040
50
60
70
Decem
ber
Janu
ary
Febru
aryMarc
h
Production(100,000 12-lbflats)Price (Dollars perflat)
Florida Strawberry Total Value 1997-2007
0
50
100
150
200
250
300
350
1997-98
1998-99
1999-00
2000-01
2001-02
2002-03
2003-04
2004-05
2005-06
2006-07
Value (millions)
Other Strawberry Cultivars to Consider – Earliglow
– Ventana – Strawberry Festival – Ovation – Oso Grande – Gaviota – Radiance – More…