The way we manage our soil is critical to the success of our crops and its impacts on the environment. We use cover crops in rotation with vegetable crops as management best practices to support high quality production. These crops are not harvested like vegetables but rather are grown and left in the field to nourish soil biology and to improve soil health. We are intentional about how we plan these into crop rotations, and we strive to minimize the amount of time soil is bare of plant cover during the year.
Cover crops provide many important services:
- Add carbon to the soil to feed microbes and sustain soil organic matter.
- Outcompete and smother weeds.
- Reset soil structure and aggregation – support soil organisms that help bind soil particles together (aggregates) and create pores and channels for air and water. This helps offset the effects of soil disturbance from tillage.
- Cycle nutrients – cover crops take up nutrients that are vulnerable to leaching and cycle them back into future vegetable crops when the residues break down.
- Legume cover crops add nitrogen, a limiting nutrient for many crops, into the soil. Microbes that live on legume roots can convert atmospheric nitrogen into organic molecules in these plants.
There are a variety of plants that work well as cover crops. We select species depending on the time of year, how long it will grow, and what the primary goal is for that field. In the spring, a mix of oats and field peas establish quickly in cool conditions and work well ahead of early summer planted vegetable crops. For summer, buckwheat is a heat loving crop that smothers weeds and flowers in just five weeks, becoming a haven for pollinators and other insects. A mix of winter rye and hairy vetch establishes quickly in fall, provides winter protection, and nourishes the soil for the next season.