Through the ages gardeners have noticed and spoken of plant marriages - the symbiotic relationships of certain plants that are often found together in nature, and seem to grow better when planted next to each other in your garden.

Early mediterranean gardeners found that planting Basil (sweet) next to their tomato plants gave them larger, healthier, better tasting tomatoes. Perhaps the tomatoes' roots absorb some root exudate of the basil, or "breathe" some secretion of this sweet smelling herb. Or, as in the case of the pigweed, the deep roots of a plant will bring nutrients up from the subsoil to the benefit of the entire garden.

Although the belief in companion planting is widespread, even its staunchest advocates aren't always certain what causes this material benefit. In some of these plant relationships it is merely the physical characteristics of the plant itself that prove beneficial. For this reason marjoram planted here and there in a garden is said to improve the overall flavor of your vegetable crop.

Certain plants have properties that ward off insects or deter weeds. There is scientific evidence for example, that the marigold keeps the soil free of nematodes and other insects such as the tomato worm.

Following are more companion plants and their beneficial relationships:
Beans: Interplant with potatoes. Aids the growth of most other vegetables.
Beets: Improve the production of onions.
Borage : Attracts bees, deters tomato worm, and gets along well with tomatoes.
Cabbage: Helps peas, lettuce and onions.
Celery : Leeks, tomatoes, bush beans, cabbage.
Chives : Planted around the base of fruit trees will discourage insects from climbing the trunk. Companion to carrots.
Cucumbers : Do especially well in close company of beans, peas, corn, radishes and sunflowers.
Dill : Improves the growth and health of cabbage. Dislikes carrots.
Fennel: Keep away from your garden, fennel is disliked by most plants.
Garlic : Improves the growth and health of roses and raspberries. Deters Japanese beetles.
Henbit: Is said to be a general insect repellent.
Horseradish : Plant at corners of potato patch, deters potato bug.
Kohlrabi : A member of the turnip family. Likes beets as company.
Lemon Balm: Attracts bees for pollination. Keep under control.
Marigold: The workhorse of pest deterrents. Plant throughout the garden to discourage beetles, nematodes and other insects.
Mint : Companion to cabbage and tomatoes, improves health and flavor while deterring white cabbage moth.
Nasturtium : Plant under fruit trees. Deters aphids and squash bugs.
Onions : Good with beans and protects lettuce against slugs.
Painted Daisy : Keeps aphids off itself and neighboring plants.
Parsley : Like asparagus.
Peas : Help the growth of all plants. Adds nitrogen to the soil.
Radishes : Serve as a general aid in repelling insects.
Rue: Keep rue away from basil. Improves general condition of roses and raspberries. Hung in a bunch near the door repels flies.
Sage : Contributes to the growth of rosemary, carrots, cabbage, peas and beans.
Spearmint: Scattered on pantry shelves and closets it will prevent an infestation and repel clothes moths.
Soybeans: Like peas, soybeans seem to promote the growth and overall health of a garden.
Sunflower : Assists the growth of beans and cucumbers.
Tarragon : Good throughout the garden.
Thyme : Deters cabbage worm.
Tomatoes : Aid onions, chives, parsley, marigold, lima beans and asparagus.