An Introduction to Cover Crops

Benefits of Cover Crops

As part of this week’s series on integrated pest management systems and reducing the need for chemicals in the garden, here is a look at the practice of growing cover crops for the benefit of the soil. Cover crops help to prepare the land for the growth of the main crop. The many benefits of cover crops include increasing soil fertility, weed suppression, and increased biodiversity. The roots of the cover crop create small pathways that water can go through. These pathways increase water infiltration and retention thereby reducing runoff and protecting our waterways. Additionally, roots help break up compacted soils. The change in plants grown in the plot can help break up pest and disease cycles. Cover crops also provide a home for beneficial insects year round. Rather than leaving a field to fallow, growing a cover crop increases the total carbon sequestered in a year and suppresses weeds.

Each cover crop is different and can provide different benefits to the garden. For example a legume cover crop, such as clover, adds nitrogen back into the soil through the process of nitrogen fixation and suppresses weed growth. A cereal cover crop, such as rye, on the other hand is great for loosening up compact soil and suppressing weed growth. Other common cover crops include buckwheat, hairy vetch and sorghum.

Choosing a Cover Crop

When it comes to picking out a cover crop there are a couple of factors to think about. We recommend checking which crops fit well with the main crops’ growing season and make sure that they are complementary plants. Cover crops are generally grown in the off season and mowed down in preparation for planting the cash crop of choice. Conventionally, after mowing down the cover crop, it is then tilled into the soil. Some farmers these days are leaving the clippings on top of the soil after mowing the cover crop, as a part of no till farming. Some plants can have negative impacts on the successional plants. It all depends on which plants play nice together. For more detailed information on which types of plants work well with different cash crops check out the links in the references section.