Companion Planting

I recently gave a presentation at the Somerville Garden Club about growing edibles in containers. After putting together an herb garden and a Tomato-Basil-Nasturtium pot, I spoke briefly about how to decide what to plant together in one pot. With so many delicious and beautiful choices, a few guidelines can make the process more manageable.

Much of the information on plant relationships (aka Companion Planting) is anecdotal. This is not at all to say that it is mumbo jumbo, but it does account for some variations in information from one source to another. Quantifying the affect of one plant upon another is tricky business, especially when there is an endless list of ever shifting variables that contribute to a plant's sucesses or demise. However, traditional planting groups, such as the Three Sisters (corn, beans & Squash) of Native American gardens prove to be wonderful companions, in the ground, on the plate, and in our bodies. This list, found on the ATTRA website, is a good place to start learning about what plants tend to get along in the garden.

Generally speaking, you want to group plants according to their needs: sun, moisture, pH. The one exception to this rule is that you don't want to plant a group of heavy feeders, like tomatoes and broccoli together. Also, you want to consider competition for root space, so growing beets and radishes together, for example, might not be the best use of space.

Another factor to consider when grouping plants in your containers is pests. Here is another table of companions to consider, whether you are battling it out with aphids or rabbits.

For more reading on Companion Planting, check out Carrots Love Tomatoes, by Louise Riotte. It is filled with tips on growing all kinds of edibles, from Asparagus to Walnuts.