Companion planting is a natural method of pest control or fertilisation where crops that are beneficial to each other are planted together. Tree fruits benefit from a different range of companions than cane fruits like blackberries or soft fruits like strawberries. By following general guidelines the home fruit grower can cut pesticide use, which may be dangerous to children, pets and the environment.
Companion Planting Methods
Growing fruits and beneficial plants together is intercropping. Strawberries companion cropped with rows of legumes (alfalfa, clover or beans) would be one example. Legumes are turned under after the growing season and rows shifted the following year. The berries benefit from the nitrogen added to the soil by the tilled-in legumes.
Underplanting is intercropping by planting companion plants directly under and around fruits. The plants can be food crops intended to be lifted and eaten later, or ornamentals left to reseed themselves. Underplanting with food crops benefits gardeners by utilising two tiers of growing space in the same plot.
Plants that attract bees and other nectar feeders benefit fruits by drawing pollinators. Using a border of attractant flowers or herbs is one way to ensure abundant fruit.
Trap cropping uses plants that pests prefer planted next to fruits as a lure.
Plants That Benefit Fruit
Marigolds and calendulas repel nematodes. Root-knot, lesion, ring, dagger, needle and citrus nematodes all infest fruit. Plant marigolds throughout the fruit orchard or around cane fruit and strawberry patches to repel them.
Tansy is said to repel ants that feed on leaves or sap and herd aphids. It is recommended as a deterrent for cutworms that cause leaf damage to cane fruits. Tansy is also a deterrent of some pests specific to raspberries. Use it as underplanting for cane fruits or fruit trees.
Garlic and onions repel codling moths, peach borers and aphids. Plant them around any fruit. An added benefit is that they deter rabbits, which eat fruit tree bark and cane fruit leaves.
Clover as a cover crop not only fixes nitrogen, it also repels wireworms that feed on planted seeds and the roots of many plants. Plant it around fruits and mow it for curing, or plant and till it under.
Fennel, chives, mint and garlic are all said to help control slugs. Plant them around cane fruits and strawberry beds or between rows of fruit trees.
Catnip, rosemary, dill, basil, garlic, nasturtiums and hyssop are some of the plants that repel cabbage loopers, a serious melon pest. Planting dill or basil with nasturtiums will also repel whiteflies and spider mites.
Companion Cropping Tips
Intercrop rather than monocrop. Massed plantings of one variety are easier for pests to home in on. If you are "square foot" gardening plant alliums, tansy or other companion plants as part of each square. Use companion plants in small gardens by bordering beds or planting them in tubs with dwarf fruit trees. Plant trap crops like radishes in tubs so that they can be easily disposed of, pests and all.