If you’ve ever felt confused about which plants grow well together, or where best to site them, take a page from the companion planting handbook. This technique dates back thousands of years and has recently regained popularity thanks to a revival of organic farming methods. Planting species that help each other out is a fantastic way to get the most from your plants using their natural characteristics, and it greatly reduces the need for harsh chemical fertilizers and pesticides.
This ancient method of companion planting grows squash, beans, and corn together to maximize productivity. The corn gives the beans support, the beans fix essential nitrogen into the soil, and the squash suppresses weeds. First, let the corn grow two feet high. Next, plant the beans. When they establish, plant squash around the outside and water weekly. This method works best in the milder climates of USDA hardiness zones 4 through 8 and with full sun. Save seeds from all three plants to propagate.
Some plants combine as well in the garden as they do in meals after harvest. Basil deters aphids and attracts helpful pollinators. It’s best to start the tomatoes first, inside or out, in well-drained soil with full sunlight. Next, plant basil shallowly, about six inches away. Water everything well with a seaweed fertilizer. This technique works for the varying temperatures of USDA hardiness zones 2 to 11, and it's easy to propagate both plants from cuttings. Watch out for wilting and brown spots.
Garlic protects raspberries from fungal infections and keeps aphids away. Plant raspberry canes outdoors, about two feet apart, in sandy or loam soil with well-rotted manure. They prefer full sun or partial shade and the milder climates of zones 4 to 8. Plant garlic nearby, then water both well. One raspberry bush should thrive for 10 years, but it's better to buy new canes when you're ready to expand, rather than trying to propagating them.
Strawberries are a rewarding plant to grow if you can fend off your insect competitors! Thankfully, borage works wonders to repel them, attracts pollinators, and even improves the flavor of the berries. Borage self-sows outdoors in most well-drained soils if given plenty of sun. Space one plant every four feet or so around a sunny strawberry patch and water moderately, using mulch in winter. This combination works well in the warmer zones 5 through 10. Be alert to signs of powdery mildew. You can always divide the healthiest strawberry plants to propagate them.
The chemical makeup that gives horseradish its pungency also helps repel potato bugs. A little horseradish goes a long way in the kitchen and the garden, so plant it in containers to prevent it from self-propagating. Space the potatoes 12 inches apart, in well-drained soil, in full sun or partial shade, preferably in moderate zones 3 to 9. Sink the containers into the soil every few feet. Water sparingly for the first two weeks and moderately after that. Look out for bacterial leaf spot and brittle root on horseradish plants, along with potato blight on its companion.
Companion planting benefits flowers, too. Edible geraniums are great for preventing weed growth and deterring rose chafers. This duo can be grown in full sun, with well-drained, enriched neutral soil in a container or a flower bed. Plant them outdoors in the temperate climates of zones 5 to 8. Both plants can be propagated from cuttings. Be alert to leaf spot in both species.
Comfrey helps maximize your harvest, as its flowers encourage pollination. Plant it around the base of apple, cherry, and other fruit trees in medium clay to loamy soil. Comfrey tolerates dappled shade, whilst the tree itself will prefer full sun. This method suits the milder climates of zones 4 to 7. Keep the soil moist but not soggy while your companions are establishing. Both plants can be propagated from cuttings. Look out for signs of comfrey rust and apple scab, slugs, and snails.
Chives are simple to grow, will fend off carrot flies, and also improve the taste of your carrot crop. Both plants like full sun, well-draining soil, and will do well across zones 3 to 9, depending on the varieties you choose. When planting, intersperse each row of carrots with a row of chives, then water moderately. Remember that aphids and mildew can cause problems. A light mulch will help to retain moisture and reduce weeds. Simply divide up chive plants to propagate them.
Aromatic dill defends cucumbers against pests and attracts pollinators and helpful predators. Plus, you’ll have two key pickling ingredients growing side by side! This combination works well indoors in colder climates, or outdoors in zones 4 to 11. Choose well-drained, slightly acidic, loose soil in full sun. You should water them frequently in warmer weather and occasionally add a liquid feed. Be alert to hornworm and carrot motley dwarf disease on your dill plants, and powdery mildew on the cucumbers. Save the seeds from both plants for propagation.
This pairing works brilliantly because the roots of each plant sit at different levels in the ground. Plus, lettuce helps to suppress weeds that would otherwise grow up between the onions. Choose a site with well-drained soil and full sun and keep the soil moist. Sow alternate rows from seed in most climates between zones 2 and 10. Watch out for aphids, caterpillars, onion flies, onion white rot, and lettuce damping off.