Planting Vegetables: Going Beyond Tradition

By George Graine, Fairfax Master Gardener
“It seems to me an utter waste of words to argue whether vegetables, if one genus or an identical kind, are species or varieties.” William Herbert in Amaryllidaceae, With a Treatise on Cross-bred Vegetables (1837)

How often have you seen a package in the grocery store indicating new and improved? This saying could just as well apply to a new book –“Plant Partners: Science-Based Companion Planting Strategies for the Vegetable Garden” by Jessica Walliser (Storey Publishing, 2020). To be clear, companion planting is not a new idea. However, the importance of science-based research was often overlooked or may not have been fully understood in the past. As an example, more than 45 years ago Louise Riotte wrote a best seller (more than 800,000 copies in print) called “Carrots Love Tomatoes: Secrets of Companion Planting for Successful Gardening.” The introduction to Walliser’s book sets the tone for what to expect in her up-to-date book for a gardener who desires to maximize and experience the best garden possible. She leads us on a journey towards “a way that approaches the garden as an ecosystem comprising many different complex layers of plants, fungi, and animals, all of which are connected to a massive web of life.”

In other words, there is a lot more to companion planting than simply putting several different types of plants together with the expectation that they will enhance growth and belay the destruction of your plants due to pests and/or disease. Although this is still important, we now know, based on research, experimentation and more, that the new way for plant partnerships has been shown to be a definite improvement. Simply putting plant A adjacent to plant B and hoping for the best outcome is akin to deciding ahead of time which horse will win the Kentucky Derby. The point of “Plant Partners” will become your road map with a way to “improve plant health, yield, and productivity.” The book which includes eight chapters, although independent of one another, is written as a building block. Each will lead to your success in the garden. Of course, you can meander about the chapters, but omitting a chapter is not a good plan. Each contains valuable information, some of which may be new to you, because you may have previously received poor information or bad decisions based on erroneous information (myths?).

These days the word ecosystem has taken on many political considerations. For gardeners we need to deal with a wild ecosystem. We need to understand and manage as many components as possible because the complexities are in constant interaction, and we often are not aware of what is happening at any given moment of time. For example, you will read chapters on many different ways to manage weeds, pests and plant diseases. As you read “Plant Partners” you will become acquainted with the concept of biological control. That means attracting and supporting beneficial insects. Beyond the obvious, the book includes information on how to improve soil fertility or structure (no till gardening vs. the negative impact of using another means of soil cultivation such as a rototiller). In addition, plant partners will also enhance your garden’s aesthetics. Details of these benefits are clearly explained in the various chapters of the book.

Each chapter begins with an introduction to the problem, followed by several research-based plant combos and other strategies that use companion planting as an effective tool to solve a particular problem. The importance of an ecosystem-based approach to the modern landscape tends to refine older planting methods. In doing so, you will generate benefits that heretofore were probably not considered or thought possible. You will become a more successful gardener by examining the ways plants influence each other. Furthermore, the emphasis on environmentalism should not be ignored. Leaving aside the arguments for and against global warming/climate change, gardeners need to understand that the soil is considered an ecological system. You will actually be supporting bio-diversity by filtering rainwater, sequestering carbon and providing many other services noted in the book. To understand this terminology is to know there are many different ways of approaching a garden from past practices.

The old concept of a vegetable garden that looked like a mini-farm with row upon row of the same crop needs to be changed (challenged?). This old way is a monoculture and it is no wonder that farms have a variety of problems. As gardeners we do not need to mimic the straight line rows of vegetables. Mix it up a bit and consider bio-diversity — vegetables, fruits, herbs and flowers all growing together. This is not heresy; this is diversity. Now you will be supporting pollinators, deter plant pests and help to limit soil nutrient depletions. Aside from all the goodness that can come from plant diversity, consider how attractive such a garden will become. Walliser includes seven benefits of companion planting. Perhaps a better word is planting strategies. These include reduction of pressures caused by (1) pests, (2) weeds, (3) disease and (4) improvement in soil fertility and soil structure, (5) pollination, (6) biological control and (7) not to be forgotten — aesthetics.

Rather than comment on the more obvious individual chapters that deal with management of weeds, pests, disease and soil preparation and conditioning, let’s turn to a less understood part of gardening, that is, biological control and pollination. These are the last two chapters in the book and they are both critical to your success as a gardener. Biological control is a way to attract and support beneficial insects, those that tend to keep the “bad” bugs in check. The point is the need to achieve a semblance of balance to your garden in a natural way. Doing so will reduce the need for pesticide control. Consider the use of “… one living organism to help control the population of another.” This is really a good vs. evil contest where you hope to repel the baddies. In order to achieve biological control, you might need to consider the creation of “… a habitat that’s favorable to the insects, and by providing them with any necessary food sources, not by intentionally releasing insects into the environment.” More simply put, you should “invite” beneficial insects that will consume undesirable insects. These predators and parasitoid insects will become a force that needs to be encouraged in order to maintain natural pest control.

Recently, we have heard a lot about pollination but sometimes the rhetoric does not always agree with reality. Of course, there needs to be a match between the plant and a pollinator. Although the chapter on pollination is heavy on different bee species, know that many other insects also play a part in pollination. Additionally, it is important to know and acknowledge that insects tend to be plant specific regarding pollination. This means that plant diversification is the key to your success. This will foster a thriving insect population which in turn will aid your companion planting.

In summary, the point of this book is “… to become better gardeners and build healthier, more productive gardens.” Give yourself an opportunity to grow the best garden ever. You will not regret reading this book and following the many suggestions (that might also dispel some myths along the way).