Strategies for Site Selection of Orchards & Vineyards Eric T. Stafne Associate Extension Professor Fruit Crops Specialist Mississippi State University Poplarville, MS
You can have the most beautiful plant in the world, but if it won t survive outside, it s worthless.
Hardiness Zone Map
Climate Scales Macroclimate large geographic region Mesoclimate local climate Microclimate specific environment around the plants Related to plant growth and development postsite 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
Length of Growing Season Some fruit crops may not ripen if growing season is too short Some grapes (especially red varieties) need longer season to fully ripen Some pecan varieties will not ripen until November or later thus being potentially exposed to shuck freeze damage http://northernpecans.blogspot.com/2011/11/whywont-some-pecan-shucks-split-open.html
Chilling Requirement A chill hour can vary depending on the model used, but the most common model defines it as the number of hours below 45 F This is a requirement for the plant to satisfy its dormancy and thus to grow and fruit normally the following year In regions where cold temperatures are more common, plants can remain in a quiescent (waiting for a warm up) phase even after their chill hour requirement has been met However, in warmer climates this may not be the case, so early flowering is a problem in low-chill varieties
Frost Can be damaging early in the growing season (bloom) and late in the season (pre-hardening off) Choose sites with low likelihood of these events Photo by B. Carroll, Oklahoma State University
Frequency of Extreme Low Temps Some fruit crops are not very winter hardy Very important for growing species/varieties on the fringes of their adaptation Often other varieties or species are available to overcome this issue
Citrus Cold Tolerance ( F) Kumquat 16-17 Satsuma 18 Calamondin 21-23 Orange, grapefruit 23-24 Lemon 26-27 Lime 28 Fruit potentially damaged below 32 F.
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 Primocane-fruiting blackberries Red raspberries (esp. fall-fruiters) Strawberries
Primocane-Fruiting Bramble Varieties Not recommended for commercial production, rather for home garden use and limited commercial trial Poor performance for primocane crop in high heat Heat in late July to early Sept. greatly reduces fruit set, quality, and yield Appears that temps of ~85 o F for several consecutive days cause these problems, and even later-season cool temperatures do not bring the fruiting potential back strongly
Precipitation What is the average annual rainfall? When does it normally fall? Is drought a common occurrence? Is flooding a common occurrence? Many fruit species do not tolerate standing water for extended periods of time (for example: stone fruits and blueberries) Some fruit species can tolerate drought conditions, but not for long periods of time (for example: pears, pecans, blackberries)
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 orchard/planting area One of the most important considerations before planting In much of Mississippi look for relative elevation on site and plant near highest point Important for frost mitigation
Low Elevations More prone to frost Less air movement Poorer water and air drainage More prone to disease Photo Mississippi State University Extension Service
Topography Includes the absolute elevation of a site How many feet above sea level?
Slope The percent inclination or declination that varies from horizontal Slight to moderate slope is desirable Important for cold air drainage Also for water drainage Steep slopes (>15%) not recommended due to difficulty in equipment use and erosion potential
Water Drainage Surface drainage is most important; avoid standing water Internal drainage is related to soil characteristics Stone fruit and blueberries are intolerant of wet soil Best planting location often is on top of a hill or on a slope Raised beds compensate for poorly drained soils
Good Drainage Situation Photo Mississippi State University Extension Service
Poor Drainage Photo Mississippi State University Extension Service
Air Movement The more air drainage, the better Air movement provides disease and frost protection Avoid hedgerows on the lower side of the orchard
Aspect In reference to the slope what is the prevailing compass direction that the slope faces? Aspect affects sunlight angle interception Not as important as some other considerations If possible, eastern exposure (or NE, SE) is better than western exposure
Aspect Attributes East = early morning sun that dries off foliage, starts photosynthesis earlier, cooler, later budbreak in spring West = hottest, late day sun exposure South = also hot during summer, may promote earlier budbreak in spring, longer growing season North = cooler during summer, later budbreak in spring, colder in winter, shorter growing season
Light Requirements Full sun is ideal Morning sun is preferable to afternoon sun
Prior Land Use Compacted soils Prior crops grown on site Nematodes Root rot fungi Pesticides used before
Soils For Fruit & Nut Trees Depth Effective rooting depth May be limited by rock, water Minimum of 3 feet in most cases Slightly acidic soil best Drainage Internal: berm, perk test External: slope to open area http://www.nrcs.usda.gov/wps/portal/nrcs/det ail/ak/soils/surveys/?cid=nrcs142p2_035915
Soil Types http://www.extension.umn.edu/yardandgarden/yglnews/ygln-may0105.html
Soil Characteristics Ideal soil is well-drained with adequate waterholding capacity Sandy loams are best Poor soil is poorly drained (internally or externally), and ph is not correct for the crop Photo Mississippi State University Extension Service
Soil ph http://www.lsuagcenter.com/en/lawn_garden/home_gardening/understanding+and+improving+soil+fertility.htm
Pests and Other Threats Disease Insects Weeds Animals Birds Allelopathic plants Neighbors
Variety Selection Adaptability to your area - very important Disease resistance Self-pollination versus cross-pollination Desired harvest date Taste, sweetness, size, texture, etc.
The Variety Equation What does it take to select and maintain an appropriate variety? AV = [(G x E) +((SS x M) + LE))]xL where: AV = Appropriate Variety
G = Genetics The variety must have the necessary genetic elements to succeed
E = Environment The environment will interact with the genetic components of the variety to impact the outcome, i.e. yields, quality, and survival
SS = Site Selection Fruiting plants placed on the wrong site, including considerations like water availability and quality, soil quality, nutrient availability, air and water drainage, accessibility, etc. will dictate final outcomes
M = Management Good management can help offset some factors such as less than optimal site selection and improve plant health and fruit quality
LE = Learning and Education Education should be a never ending task for a fruit grower, but a good knowledge of the basics should be garnered before putting a plant in the ground
L = Luck All of the best laid plans can be disrupted with bad luck drought, freezes, broken pumps, plugged emitters, birds, plague of locusts, etc., because once your luck turns to zero, so does your AV
Some Examples Concord grape doesn t tolerate heat well, susceptible to PD Flame Seedless grape susceptible to PD Highbush blueberries not heat tolerant, high chilling requirement Sweet Cherries do not tolerate heat, high chilling requirement Citrus cannot tolerate much cold
News You Can Use Mississippi Fruit and Nut Blog http://msfruitextension.wordpress.com/ My email: estafne@ext.msstate.edu (best option) My phone number: 601-403-8939 Twitter: @EStafne