Mid-Missouri's long growing season allows us to have several plantings. Some plants are planted in the spring (brassicas, greens, cabbage, bush beans, etc.) and can be planted again in the fall. But what do you do with that area between plantings. The summer crops are planted somewhere else. If you don't plant something there, I can assure you weeds will grow there. So what can you do with that space? Plant buckwheat, that's what. Buckwheat is a fast and easy-to-grow cover crop.
There are many benefits of planting cover crops. They cover the soil and, in doing so, suppress weeds and prevent erosion, bring up nutrients from deep in the soil to nourish the topsoil, improve soil structure, feed beneficial fungal networks, and attract pollinators and beneficial insects, just to name a few purposes. Most cover crops are planted in the fall or early spring. But buckwheat thrives in the summer and can provide a host of benefits to your garden, especially in those fallow areas in the middle of the season.
Most fall cover crops are meant to grow over many months, while buckwheat is ideal for summer crops because it grows so quickly. Only needing around six weeks from seed to maturity, if you only have a few weeks that you need to cover your ground between plantings, buckwheat is the perfect cover crop choice. Although best results come from six to eight weeks of growth, even a few weeks of growth can provide benefit, just not the flowers. It can grow to three feet tall in about four weeks.
Vegetable growers were some of the first to make use of buckwheat as a cover crop because the growing season of buckwheat fits in well -- after early vegetables, such as potatoes and spring greens, and before fall-planted vegetables or winter annual covers. Vegetable growers also like the way buckwheat attracts pollinators and beneficial insects if allowed to flower, while providing a quick ground cover. Moreover, buckwheat is easy to manage on a small scale in a vegetable garden since it can be broadcast-established and easily killed by mowing, rolling or tilling.
The soil improvement provided by buckwheat has long been noted but could use more research. Buckwheat appears to be uniquely good at making phosphorous more available in the soil; phosphorous is one of the three main soil nutrients plants need, along with nitrogen and potassium. All soils have some phosphorous in an available form plant roots can absorb, but the majority of soil phosphorous is in an unavailable (insoluble) form the plants can't access. Buckwheat roots release acidic compounds that help convert some phosphorous from the unavailable to available form.
Besides making phosphorous more available in the soil to the next crop grown after buckwheat, many gardeners have reported buckwheat improves the tilth of the soil. This means the soil becomes easier to work or plant into.
Buckwheat can be seeded directly into a clean bed or you can gently till the soil and wait about a week for organic material to decompose before seeding. Some suggest the bed be watered ahead of time and then scatter the seed over it at a rate of about one pound per 500 square feet of garden space or about three ounces per 100 square feet. Then rake and water the seed in. I have not watered before just after planting with good germination, but I might try watering a day or two ahead next time.
I have been experimenting with cover crops for several years, maybe 10 or 12 actually, and I think they are well worth the extra effort. I hope you will try some this year.
Peter Sutter is a life long gardening enthusiast and a participant in the MU Extension's Callaway County Master Gardener program. Gardening questions can be sent to [email protected]