Companion Planting Guide

Companion planting is the practice of growing certain plants together for mutual benefit. Good companions can help deter pests, improve soil, and maximize garden space.

Classic Companion Planting Combinations

Tomatoes + Basil

Benefits: Basil may help repel aphids, whiteflies, and tomato hornworms. Some gardeners believe it improves tomato flavor.

Plant nearby: Basil, carrots, parsley, marigold

Avoid: Brassicas (cabbage family), corn, fennel

Carrots + Onions

Benefits: Onions repel carrot fly. Carrots may help repel onion fly. Space-saving combination.

Plant nearby: Lettuce, tomatoes, beans

Avoid: Dill, parsnips

Beans + Corn + Squash (Three Sisters)

Benefits: Native American technique. Corn provides support for beans. Beans fix nitrogen. Squash shades weeds.

Plant nearby: Cucumbers, melons

Avoid: Onions, garlic

Lettuce + Radishes

Benefits: Radishes mark rows and break soil. Both mature quickly. Radishes can be harvested before lettuce needs space.

Plant nearby: Carrots, spinach, strawberries

Avoid: Parsley

Cucumbers + Beans + Radishes

Benefits: Beans fix nitrogen. Radishes break soil and deter cucumber beetles. Space-efficient intercropping.

Plant nearby: Peas, corn, sunflowers

Avoid: Potatoes, aromatic herbs

Pest-Repelling Plants

Plant Repels
Marigolds Nematodes, aphids, whiteflies
Nasturtiums Aphids, whiteflies, squash bugs
Basil Mosquitoes, flies, aphids
Rosemary Cabbage moths, bean beetles
Lavender Moths, fleas, flies
Garlic Aphids, Japanese beetles

Plants to Avoid Pairing

Some plants compete for nutrients or attract the same pests:

  • Tomatoes + Corn: Both attract tomato fruit worm/corn earworm
  • Onions + Beans: Onions can stunt bean growth
  • Potatoes + Tomatoes: Both susceptible to early blight
  • Fennel + Most Vegetables: Fennel inhibits growth of many plants

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