University of Maryland Extension

Growing Organic Fruit

ripening fig Asian pears on tree unripe strawberries on plants
Fig Clemson Musser Farms (left); Asian pear (center); Immature strawberries (right)

Growing Fruit Organically in Maryland

Home gardeners have more success growing small fruits organically than growing tree fruits (apple, pear, peach, plum, and cherry) organically. Three notable exceptions to this “rule” are Oriental persimmons, Asian pears and figs. Blueberries, brambles, currants, gooseberries, and strawberries, are well-adapted small fruits that can be grown without the use of chemical pesticides. In some cases, the limited use of “organic” or “bio-rational” materials like liquid lime sulfur and ultra-fine horticultural oil may be helpful. Also, backyard gardeners should know and accept that you can “eat around” some pest problems and ignore the superficial damage caused by insects and diseases that might be considered unacceptable in commercial orchards (e.g. flyspeck and sooty blotch on apples). 

To grow any type of fruit organically, you must grow healthy plants and anticipate and prevent problems. The appearance and severity of pest problems varies between neighborhoods, areas of the state and growing seasons. When symptoms of a problem are noticed you must be able to accurately identify the problem (weed, insect, disease, cultural/environmental), monitor for changes (increasing severity) and be prepared to act. These preventive techniques and control measures may be physical (e.g. pruning out raspberry cane borers, hand-picking Japanese beetles, removing diseased plants), cultural (e.g. pruning brambles to improve air circulation) or chemical (e.g. horticultural oil to smother scales.) 

However, a large number of the fruit problems observed each season by gardeners are cultural and environmental. These  include, poorly drained soil, insufficient water, nutrient deficiencies or excesses, limited space and sunlight, lack of plant  support, temperature extremes, root damage from cultivation, planting too late or early, plants not “hardened-off” properly for winter, choosing inappropriate varieties and purchasing poor transplants. 

Most organic pesticides have a relatively short effective life (residual) and may need to be applied more frequently than conventional pesticides. Despite their “natural” origin, however, it is important to remember that these products are pesticides and can also have toxic effects on humans, pollinators, and the environment.

General Planting Tips

Small Fruits
Tree Fruits

General Care Tips

Fertilizing

  • Organic fertilizers, like composted farm manure and composted yard waste can be substituted for chemical fertilizers. Foliar applications of seaweed extract, compost tea or fish emulsion are beneficial, especially when new growth begins in the spring and during bloom.
  • Most fruit plants are fertilized in spring- during or immediately following bloom. Late summer and fall fertilization may interfere with the hardening-off process and lead to winter damage. (Strawberries are an exception- they are fertilized in late August).
  • Over-fertilization, regardless of the nutrient source, can produce weak growth, prone to attack by diseases and  sucking insect pests.

Water and Mulch

  • Keep an organic mulch around small fruit plants during the growing and dormant seasons.  Remove mulches to allow soil to warm in the early spring. 
  • Keep mulches 6 inches away from tree fruit trunks during dormancy to prevent vole damage.
  • Regular watering will help prevent insect and disease problems and increase fruit size and yield.  This is especially important for young plants, during droughty periods and in late summer and early fall when next year’s buds are forming.  Soaker hoses and drip irrigation systems work very well with small fruits.

Anticipating and Preventing Problems

  • Plantings located in an area with neglected orchards will be more prone to insect and disease problems.
  • Anything that stresses a fruit plant may encourage insect (especially borers) and disease problems. Stressors include: drought, physical damage to the trunk, compacted, poorly drained soil, defoliation, winter damage, poor planting stock, etc.
  • Orchard sanitation is critical for eliminating disease inoculum and over-wintering pests. Regularly remove and discard all diseased or infested plant parts (leaves, fruits, etc.) from the ground and from the plant. Use a mulching mower to chop all fallen leaves in the fall or rake and remove them.
  • Control insect pests, like thrips, aphids, and leafhoppers that vector (spread) diseases.
  • Rogue out (remove) strawberry and bramble plants with virus-like symptoms.
  • Prune out water sprouts, unwanted root suckers and wilted canes.
  • Thin apple and peach trees when fruits begin to form, so that fruits are 6 inches apart.
  • Keep fruit plants pruned and trained to maximize fruit production, encourage air circulation and maintain plants at a manageable height. Keep bramble and strawberry rows narrow and avoid planting fruit next to a wall or fence.
  • Pick your fruit often; don’t allow fruit to become over-ripe or fall to the ground.
  • Keep weeds cut down in and around your fruit plantings to remove favorable habitats for pests.
  • Spray on a schedule for serious predictable diseases (brown rot of peaches, plums and cherries and black rot of grapes) and insects (plum curculio). 
  • Avoid Japanese beetle traps. They will increase the amount of damage suffered by your landscape and fruit plants or place them on the other side of your property, far from the target plants. Sweep Japanese beetles off of foliage and fruit into a bucket of soapy water. 
  • Paint the trunks of stone fruit trees with white latex paint in the fall to prevent bark cracking and splitting  caused by freeze-thaw cycles (especially for trees facing south).

Organic fungicides
Organic insecticides

 

 

 

 

Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2020. Web Accessibility

University programs, activities, and facilities are available to all without regard to race, color, sex, gender identity or expression, sexual orientation, marital status, age, national origin, political affiliation, physical or mental disability, religion, protected veteran status, genetic information, personal appearance, or any other legally protected class. If you need a reasonable accommodation to participate in any event or activity, please contact your local University of Maryland Extension Office.