Use Garden Space Wisely, Try Companion Planting

Companion planting and intercropping are two ways gardeners can increase yields on the same amount of space, and they can help improve the soil. Many market gardeners depend on these methods to increase profits. These two methods share some similarities, but they are not exactly the same. Companion planting involves planting two or more crops in close proximity that benefit each other in some way. Basil, for example, helps deter some tomato pests. A few weeks ago I wrote about planting cilantro in my potato patch as a way of deterring potato beetles.

Many books have been written about this concept. The internet offers a wealth of free information about companion plants. Intercropping is a similar method, but it focuses more on roots. The idea is to plant two or more crops with root systems that don’t compete with each other for nutrients. Some crops have deeper roots than others. Other crops send down a large, single tap root, while other crops grow from many smaller roots closer to the surface.

Legumes like beans and peas have the ability of taking nitrogen out of the atmosphere and depositing it in the soil. If you plan for a succession of crops, you can harvest the legumes and leave the roots in the soil, thereby providing nitrogen for a later-maturing crop.

How many different types of crops can you grow in one space? If we take nature as a guide, the answer is many – dozens perhaps. Monocultures – the practice of growing one plant species in a given area – rarely happen in nature, if ever.

Take a look at any patch of native prairie around here, like a ditch along a county road. In a few square feet, you are likely to find a dozen or more plant species – multiple grasses and wildflowers, shrubs, and the occasional tree. Last week I planted a six pack of tomatoes in my garden. I transplanted them into a bed about three feet wide by eight feet long. I staggered them in two rows towards the edge of the bed. I planted a row of bush beans in the middle. And all throughout the bed, I sprinkled some carrot seed. Tomatoes are heavy feeders and require more fertilizer.

Here’s my rationale: Beans produce their own nitrogen, so they shouldn’t compete with the tomatoes for nutrients. And carrots tap nutrients from deep in the soil. So they shouldn’t compete with the tomatoes, either. Plus, many gardeners have found that carrots improve the health of both tomatoes and beans. In addition, my hope is that the dense foliage of the carrots will act as a living mulch, retaining soil moisture and shading the surface to prevent weeds from germinating. I’ve never tried this exact combination. Hopefully it works well. If it fails, I’ll learn a lesson.

Bunching onions and radishes are very popular among market gardeners for companion planting and intercropping. You can grow a lot of these in a small amount of space. But do your research. Onions, for example, can inhibit the growth of some crops, especially beans. Some folks warn against planting radishes close to broccoli. According to this theory, plants in the brassica family, which includes broccoli and radishes, are allelopathic, meaning they exude chemicals in the soil that prevent plants in the same family from sprouting nearby. This is nature’s way of providing some spacing among plants of the same species. But in my garden, a patch of volunteer radishes sprouted all throughout my broccoli patch this spring. Personal experience doesn’t always align with theory.

Check out this article on companion planting for an introduction: https://www.almanac. com/companion-plantingguide- vegetables. But just like the news, don’t get all your information from just one source. Look around and you’ll find some patterns. Follow those patterns, and then blend in your own personal experience.