COMPANION PLANTING

Picture a patch of wild land. Then picture a modern agricultural landscape. Are they any different?

The patch of wild land is likely to host a diverse range of plant species, of varying ages, occupying a multitude of different niches. It hosts diverse animal species as well, from worms, insects, snakes, birds, and mammals down to microorganisms. It is likely to have an “organic” feel to it, displaying a much more artful, complex, chaotic “order” than is generally evident in human-designed landscapes.

By contrast the modern agricultural landscape is likely to consist of one plant species for acres at a stretch. Animal species diversity is minimal, tending toward animals considered “pests.” The landscape probably has an “industrial” or even “military” feel to it, consisting of straight lines and rectangles. If it is a typical modern large farming operation, it embodies the antithesis of wildness.

Food-growing didn’t always stand in stark contrast to wildness. It grew out of wildness. Until the advent of industrial agriculture, most gardens and farms were almost infinitely more diverse than today’s typical large-scale monocultures. Large-scale machine- and chemical-intensive farming predisposes one to certain “garden designs,” consisting almost exclusively of large patches of the same plant. But human-scale gardening, especially with hand tools, predisposes one just as strongly to diverse planting schemes and to a much closer emulation of natural “wildness.”

In natural ecological communities, many different varieties and species of different-aged plants coexist and thrive in symbiotic relationships. In keeping with Permaculture principles, the more closely we can replicate this kind of multigenerational diversity in our gardens, the healthier and more productive those ecosystems too are likely to be.

Preparing beds by hand means that we can leave still-productive plants in our garden beds when we prepare them for new crops. Perennials, biennials, seed crops, and volunteers can thus coexist with newly-planted vegetables. If any of those older individuals are ready to take out later, we can always remove them, cultivate, and replant their portions of the bed when their time has come.

Even within our new plantings, we can foster multigenerational diversity. Gardening books speak frequently of “companion planting,” but many gardeners may fail to realize just how many ways plants can be companions, and how widely companion-planting principles can be applied. In some of the best-known examples, certain companions emit chemicals that improve one another’s flavor, or attract beneficial insects that will discourage one another’s pests. (In fact, diversity in general will attract beneficial insects, confuse pests, and reduce pest damage.) But companions may also skillfully share habitat by having complementary aboveground and belowground space requirements, complementary nutrient requirements, complementary water requirements, and complementary needs for sunlight. In other words, low-growing and taller plants, deep-rooted and shallow-rooted vegetables, sun-lovers and shade-lovers, and those whose preferred pallets of nutrient and water intake do not compete with one another, will very happily coexist, as they do in natural landscapes.

Quick-growing short-term plants and slower-growing longer-term plants can also be perfect combinations. We frequently plant longer-term cooking greens, many of them biennials that will survive overwinter and continue producing into the spring, such as cabbage family members and chard, in a grid pattern which will provide optimal spacing once the plants are full-size. In between them, we plant salad starts such as lettuce, arugula, tah tsai, bok choy, spinach, etc., most of which will be ready to harvest quite quickly, and which will be ready to remove from the bed by the time the longer-term plants need the room. Mizuna mustard straddles the line between “short” and “long” term—it is a fast-growing salad green, but it also works as a cut-and-come-again vegetable that will last for a while before it exhausts itself and flowers. Even brassicas that may complete their cycle within the first season of growth, like certain cabbages, broccoli, and cauliflower, are suitable “longer-term” foundation plants in between which one can plant salad greens. Especially in the summer, salad greens appreciate the shade provided by larger plants—they can even be planted into a bed in the shadow of already-established plants with great success.

Summer and winter squash, cucumbers, and tomatoes are all plants around which salad greens can thrive before these larger plants have attained their full size. Squash, especially, is planted with significant distances between clumps, so a bed of squash can easily yield nearly a bed’s worth of lettuce before the squash plants get large enough to cover the entire area. Salad plantings between and underneath tomato plants are generally a bit less productive (because the tomato plants are transplanted at a larger size, and closer together, than the squash), but nevertheless produce salad that one would not otherwise have. Salad plantings between rows of newly-sown root crops can also yield abundantly—and/or rows of root crops, peas, or beans, can be sown between salad greens that will be harvested by the time the new plants need the space.

Root crops themselves can be companion-planted with one another. Radishes are typically sown in the same furrows as carrots, because they sprout and grow quickly and help shade and protect the slower-sprouting and –growing carrots until the carrots need more space. Radishes are also often sown with parsnips, which take even longer to germinate and grow. In both cases, the radishes must be harvested with care to avoid disturbing the longer-term crop, but the longer-term crop undoubtedly benefits from this arrangement, as do the radishes (which get their day in the sun) and the gardener (who doesn’t have to fuss as much over the carrots or parsnips, since the radishes are helping to keep them moist and protected during sprouting).

As usual, the Beetless have something to say about all this. I'VE JUST SEEN A PLACE [0] recites a litany of companions taken from published gardening texts, and, perhaps more importantly, notes some of the qualities that make crops good companions. It also sheds light on “antagonists,” a small handful of plants which actually discourage one another’s growth. We don’t place much emphasis on plant antagonism in our garden planning here, although we do try to keep fennel out of most of the garden beds, because of its reputed allelopathic (plant-growth-inhibiting) properties.

As for spacing between plants, the simple formulas and recommendations presented in seed catalogs and gardening books cannot always be strictly applied to diverse companion-planted beds. Even for single-crop plantings, recommendations vary. We tend to consider the different recommendations, and also factor in how many plants are ready or needing to be transplanted and how much bed space is available. All other things being equal, we tend to use spacing somewhere in between the dense plantings recommended in Jeavons’ How to Grow More Vegetables and the more widely space plantings recommended in the Territorial Seed Company catalog. Whenever possible, we tend to plant in the offset “grid” or “honeycomb” pattern described in Jeavons’ book, by which more plants can fit in a bed because the basic spacing pattern is based on a triangle rather than a square. In other words, the plants in each row are placed equidistant from two plants in the adjoining row, rather than lined up with one of them, meaning that the rows themselves can be closer together. (If you are still confused, consult the diagrams in Jeavons’ book.)

Crop rotation is a well-known form of “companion planting over time.” Gardening books give various prescriptions for crop rotations, which generally involve alternating the growing of heavy feeders (plants which make large nutrient demands on the soil), light feeders, and “givers” (plants which help provide nutrients to the soil). Crop rotation can also reduce the danger of pest and disease problems by not allowing their buildup in association with plants that might otherwise grow year after year in the same area. Because our garden areas are often so diverse, strict crop rotation formulas often do not directly apply; we have enough diversity in many beds throughout the course of a year that following with similar crops in the following year does not cause any problems. Strict crop rotation is most important in the case of monocrops, and is also essential when observed pest or disease buildup indicates that it is necessary. As a general rule, we try to rotate crops and “mix it up,” but we don’t get too stressed when we realize that many of the twenty different varieties of vegetables which are growing in a bed were also seen there sometime in the previous year. Diversity helps healthy plant communities thrive in the same place much longer than homogeneous communities ever could. The continued flourishing of some volunteer vegetables in similar locations year after year (see YOU WON'T SEED ME [0]) is proof that dogmatic adherence to crop rotation formulas can be not only unnecessary, but self-defeating, evidence of Small Thinking that would eliminate plants that “know where we want to be…we’re the best nutrition, and we grow for free.”

 
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