Companion Planting

Use companion planting to help thwart pests without using chemicals!

So many things in life come in pairs or groups, and form natural associations – like good friends, or chocolate and...well, just about anything. Gardens are the same way. Some plants were meant to be together because they have a way of helping each other grow and thwart off predators. This kinship is called “companion planting” and it has been practiced for years.

How does companion planting work?

Take garlic, for example. You can smell it. It isn't a strong smell when growing, but insects don't like it. If that smell wafts over a tomato patch and overwhelms the tomato smell, a bug may decide to leave your tomatoes alone. If another kind of plant attracts a bug such as a Lady Beetle, which is a big aphid consumer, then you might see fewer aphids on that plant and on nearby plants. A plant that can deal with the attacks by certain insects may be able to shield the weaker plant when planted close together.

Fall is the perfect time for planting in the Seattle area and Pacific Northwest. As you select plants for your garden, there are several flowers and vegetables that pair nicely together. Some examples of common parings include growing nasturtiums near other edible garden plants such as melons, cabbage, radishes, broccoli, beans, tomatoes, as well as apple trees. The nasturtium attracts aphids and insects that would otherwise feed on these plants. (Read more about edible gardening in our blog from March 2011.)

Petunias and geraniums also ward off bugs such as beetles and aphids, which will make your pumpkin, cucumber, and asparagus happy. Marigolds are another companion that are good at attracting ladybugs, which then eat the aphids. Even before the pilgrims came to America, sunflowers were planted near corn in order to attract the aphids and keep the corn free of bugs. They grew a lot of corn so there must be something to it.

Sometimes the opposite will happen when two plants are antagonistic. No, they don't literally fight with each other, but the chemicals or growth behavior of one can have a bad effect on the other. Oak is one such plant, which is why it is such an unlikely companion plant. It has toxins in its leaves which will harm grass and other plants if left in pile for too long.

Companion planting generally works, but as with any friendship it can be a bit finicky. It depends on a lot of tiny nuances -- your garden needs the right kind of soil, temperature, rain, shade, altitude, wind flow, location... The standard formula for companion planting may not work for you, but it’s still worth a try.

As you begin planning next year’s garden bed, go ahead and plan to include some “friendly” plants in your garden. And remember...we at Environmental Construction are here to help will all your companion planting and vegetable garden needs.

Category: Tips for Planting