Companions are plants that have compatible growth habits and share space well; allies are plants that enhance growth and ward off insects.
For a quck guide of companion plant pairings, see the table below.
BEANS: Companions: Beets (bush beans only), cabbage family, carrots, celery, chard, corn, cucumbers, eggplants, peas, potatoes, radishes, strawberries. Allies: Marigolds (Mexican been beetles, nematodes), summer savory (bean beetles)
BEETS: Companions: Bush beans, cabbage family, lettuce, onions. Allies: Garlic
CABBAGE FAMILY: Companions: Beans, beets, celery, chard, cucumbers, lettuce, onions, potatoes, spinach. Allies: Catnip, chamomile, garlic, hyssop, mint, rosemary, sage and southernwood (cabbage moth); nasturtiums (beetles, aphids); tansy (cabbageworms, cutworms)
CARROTS: Companions: Beans, lettuce, onions, peas, peppers, radishes, tomatoes. Allies: Chives improve growth and falvor; rosemary, sage (carrot flies)
CORN: Companions: Beans, lettuce, onions, peas, peppers, radishes, tomatoes. Allies: Odorless mariglds, white geraniums (Japanese beetles); pigweed raises nutrients from the subsoil to the corn.
CUCUMBERS: Companions: Beans, cabbage family, corn, peas, radishes, tomatoes. Allies: Marigolds (beetles); nasturtiums (aphids, beetles) improve growth and flavor; oregano (pests in general); tansy (ants, beetles, flying insects)
EGGEPLANT: Companions: Beans, pepers, potatoes. Allies: Marigolds (nematodes)
LETTUCE: Companions: Beets, cabbage family, carrots, onions, radishes, strawberries. Allies: Chives, garlic (aphids)
PEAS: Companions: Beans, carrots, corn, cucumbers, potatoes, radishes, turnips. Allies: Chives (aphids); mint improves vigor and flavor
POTATOES: Companions: Beans, cabbage family, corn, eggplant, peas. Allies: Horseradish planted at the corners of the potatoes patch provides general protection; marigolds (insects)
PUMPKINS: Companions: Corn, melons, squashMarigold, nasturtiums (beetles); oregano provides general pest protection.
RADISHES: Companions: Beans, carrots, cucumbers, lettuce, melons, peas. Allies: chervil and nasturtiums improve growth and falvor
SQUASH: Companions: Celery, corn, melons, pumpkins. Allies: Borage (worms), improves growth and flavor; marigolds (beetles); nasturtiums (squash bugs, beetles); oregano provides general pest protection
STRAWBERRIES: Companions: Beans, lettuce, onions, spinach, thyme. Allies: Borage strengthens resistance to insects and disease. Thyme as a border (worms)
TOMATOES: Companions: Asparagus, carrots, celery, cucumbers, onions, parsley, peppers. Allies: Basil (flies, mosquitoes), improves growth and flavor; bee balm, chives and mint improve health and falvor; dill until mature, improves growth and vigor, marigolds (nematodes)