If you think your fall gardening chores are over, think again. There’s one thing you should do before hanging up your gloves for the season: Plant a cover crop.
Cover crops are some of the most overlooked, but beneficial crops in the garden. Composed of grains, grasses or legumes, these fast-growing plants are not intended for use as a source of food, but to build good soil and replenish existing soil with nutrients. In fact, they usually aren’t harvested and are instead tilled under to put nutrients back into the soil to improve your garden next season.
Sometimes called “green compost” or “green manure” they help improve soil in a number of ways. As we know, our heavy shale and clay soils here are a gardener’s challenge. When they are in the ground and growing, they will help control weeds and erosion. Once tilled under, they improve soil health by adding organic matter and nutrients back into our clay soils, and the more you plant, the better for your soil. This should lessen your need for fertilizer come spring. Once the soil is loosened, it also becomes an attractive habitat for earthworms, which will help to aerate as well.
The decaying plant material adds organic matter into the soil, providing fertilizer for next year’s plants. If you till your crop under in the fall, it works to break up heavy soil, and will help to keep your garden soil from compacting over the winter.
There are several good choices for our area and here are just a few. Buckwheat is one of the best and is often used. This quick-growing annual tolerates poor soil and matures in 6-8 weeks. It’s good for loosening topsoil and suppressing weeds. This is one you’ll want to mow or till under at flowering, before it sets seeds so it does not become a weed in subsequent crops planted in that spot.
Red clover is another good choice that tolerates our poor soil. This deep-rooted perennial produces a lot of nitrogen. The deep roots help to break up compacted soil, and provide a good habitat for beneficial insects. Oats and peas are also commonly used. Oats establish quickly and are easily killed. They provide good erosion control. Peas provide a large amount of nitrogen and are especially useful when planted as a companion crop.
Planting is easy. Begin by removing your summer annuals or vegetables from the area in which you want to plant your cover crop. Rough up the surface so that the seeds don’t blow or easily roll away. Broadcast your seed over the surface, taking care to scratch it in so that the birds don’t feast on your crop before it has a chance to grow. Water if needed. Now is the best time to plant, while there are still warm, sunny days and they have time to grow.
Maintenance for these crops is relatively easy, depending on what you’ve selected. Most use little water and require little attention.
Once the seed heads emerge on the grain crops, or the flowers emerge on the others, it’s time to kill them. It’s easy. Cut them at the base of the plant before the top growth gets out of control and they set seed, or you could end up with a mass of undesirable weeds in your garden next spring. Smaller crops can be tilled directly into the garden. Larger ones can be cut with a lawn mower or weed trimmer depending on how large an area you have and how big they have grown. Wait a few days to let them dry, then dig or till them into your garden. The decomposition of the crop over the winter months will provide great nutrients for your garden next spring, hence the name “green manure.”
This improved, healthier soil, will be a great place for your plants next spring. Not only will they have the advantage of green fertilizer already in place to start them once they are planted, they should grow strong and healthy making them more disease and pest-resistant. Think about it. The weakest are always the ones that struggle, but healthy plants grow better and produce more throughout the season.
Cover crops can be one of the most important plantings in a gardeners year, and also one of the most beneficial. A little seed and effort now can go a long way to having a happy, healthy garden next spring.
Gail Vanik can be reached at 970-565-8274 or by email at fourseasons@animas.net.