Every year we are intrigued by cover crops and find ourselves wondering why more farmers don’t utilize them. Late summer and fall is an important time of year when we start to wrap things up for the growing season, making our final passes through the fields and putting them to bed for the winter. We remove the mulch and irrigation lines, take down tomato stakes and chop any remaining plant material (such as broccoli stalks) in the field. Starting in mid-late summer, as soon as a crop is finished, we start this process with the goal of getting a cover crop planted as soon as possible. We’ve been planting cover crops since August, so many fields are already covered with a lush blanket of green growth. Cover crops are a very important part of our production system and are important for maintaining the health of our soil as well as investing in future crops we’ll take off the land.
|Richard kneeling in a cover crop planting|
|Field planted with a cover crop mix of annual rye grass,|
oats, crimson clover, Japanese millet and Austrian winter peas
This year we’ve chosen to diversify our cover crop plant mixes. We have two different mixes. The first mix is a combination of four different plants that have the ability to overwinter. This means they will start to grow again in the spring time. We plant this mix in fields that we do not plan to plant early crops in. This mix includes hairy vetch and mammoth red clover which are both legumes. The other two components are annual rye grass and cereal rye. Each component of the mix has a specific purpose. The legumes are important because they have the ability to take nitrogen from the air and fix it in the soil. Annual rye grass is a fast-growing, aggressive plant that can out-compete weeds. While it’s part of the overwinter mix for this purpose, it’s actually one component that will not come back in the spring. Cereal rye is important because it takes up the nutrients, including the nitrogen synthesized by the legumes, and acts like the sponge to hold onto them. They release them into the soil as needed, or at the end of their life cycle when we cut the cover crop and work it back into the soil.
|Austrian winter peas, rye and clover in our cover crop mix.|
Our standard operating procedure when we finish harvesting a crop is to immediately follow with the chopper to break down any remaining plant material, then do a light disking. Next, we spread compost and then the cover crop seeds are planted. This happens fast and the whole process can be completed in 24-36 hours! This is very time-sensitive and every day matters because you really want to maximize the growth of the cover crop while the fall days are still warm. Of course we need moisture in the soil to germinate the seeds, so sometimes we dance with the weather and try to time the seeding right before or after a rain.
Using cover crops is a very efficient way to hold and add nutrients to the soil. Once the crop is planted, everything happens in place. There is no additional need to haul or spread additional fertilizer…the plant does all the work for us! Management, teamwork and timeliness are key components to making this all come together.