Cover crops are the best way to add organic matter to the soil. You throw out the seed and the plants grow, harvesting what they can from the sun, the air and the rain. Then they return their nutrients to your soil, all while you are busy elsewhere. If only it was that easy.
The goal for managing cover crops in the spring with a tiller is to turn it all in before it gets too tall. To get the maximum benefit from these crops, however, you would want them to grow to their fullest and harvest all that great biomass. At that point it is all too much to handle for a tiller. That’s okay, because it can be managed with hand tools in your garden. You can cut it and leave it lie as mulch, or put the material in the compost pile. Knowing when the right time to do that is the hard part. I can give you some guidelines to follow, but the learning is in the doing. Your own experience is your best teacher.
When the cover crop has reached its most biomass is when it is flowering. In the case of wheat and rye, you will see it shedding pollen. At my place in zone 7 that normally occurs around May 7, about 10 days after our last expected frost. Because of the crazy no-winter weather we’ve had this year, it occurred a few weeks earlier. At that point it can be cut. I use a Japanese-style sickle for this. Another option is to let the crop grow until it produces mature seed. In the case of rye and wheat, you would have a good harvest of straw for compost material, along with the seed to eat or replant. Some crops become a nuisance when you let them grow out to seed. Amaranth comes to mind, as does hairy vetch.
The cover crops I have to manage this spring are cereal rye (sometimes known as winter rye), wheat, Austrian winter peas, hairy vetch and crimson clover. The winter peas, vetch and crimson clover are legumes, meaning they fix nitrogen from the air in their roots. Their foliage doesn’t last as long as mulch as does the rye. Usually the soil can be planted into soon after the legume plants are cut at flowering. Cereal rye (different than ryegrass) puts down a much larger root system, adding organic matter right where it is needed. Wheat is similar to rye, but I get more biomass with rye. You need to wait two weeks after cutting rye and wheat at pollen shed to transplant into it, because of that increased root system. Actually I never cut wheat early. Since rye grows taller and produces more biomass, I plant it for that purpose. I only plant wheat when I want to let it grow out to seed to eat. Choosing the right crops for your garden is a learning experience. You can get some help from the book Managing Cover Crops Profitably, 3rd edition. Be sure to read the text and not just look at the charts. Some crops that look great on the charts have surprising details that you need to know. One of the benefits of having a variety of cover crops in your garden is that they are not all cut at the same time. That provides places for the beneficial insects to take refuge when part of their habitat is being changed.
My video Cover Crops and Compost Crops IN Your Gardenshows me in the garden managing cover crops in the way I’ve just explained. You can find more tips about managing spring cover crops without a tiller at Homeplace Earth. May your cover crops grow, your garden be bountiful, and you find time to enjoy it all!