Plants make great neighbors, especially to each other. They repel harmful insects, create shade and windbreaks for each other, help each other pollinate and even support each others climbing habits. By finding them the right companions, you can enhance the growth and success of every tree, shrub, vegetable and flower in your garden.
There are a number of ways to use companion plants to your advantage. You can space them throughout your garden, plant them as a boarder to protect the plants inside (like pest repelling marigolds) or use them as decoys to lure harmful insects away from other plants. If your garden space is limited, plant them in pots so you can move them as you need them.
Good repelling companions are often herbs. Garlic, for example, helps bush beans repel aphids. Catnip next to eggplants will repel flea beetles and chives under an apple tree will discourage apple scab. Strong smelling herbs that repel a variety of pests include anise, cilantro, dill, scented geranium, mint rosemary, sage, and tansy.
Some herbs improve the flavor of their companions. Borage is said to improve the taste of strawberries and basil and thyme improves the flavor of tomatoes. Other herbs simply enhance the growth of their companions, like chervil improves radishes and summer and winter savory boosts onions.
It's good to note that while some plants enhance the growth and success of their companions, others can actually hinder it. Dill, for example, should be planted away from tomatoes, sage away from onions and garlic away from peas and beans. Although marigolds, sunflowers, and wormwood enhance some plants, they hinder the growth of many. Once you decide on the types of plants you want to grow, consult with the many books and resources available to find out which plants make good companions for them.