Cover crops – diversity for living soil

Cover crops play an important role on our farm in maintaining and improving soil fertility. They are grown between two main crops and fulfil many useful functions: they protect the soil from erosion, improve soil structure, promote soil life and suppress weeds.

As oilseed rape is a fixed part of our rotation, we deliberately avoid brassicas in our cover crop mix to prevent rotation diseases such as clubroot. Instead, we use a diverse mix of non-brassica species with specific properties.

A key aim is to cover the soil quickly to minimise evaporation and erosion – this is where niger (ramtil) comes in, which emerges quickly and closes the surface. Linseed, with its fine root system, is ideal for loosening and aerating the soil. Phacelia not only adds attractive flowers to the mix but is also a valuable source of nectar for insects. Clovers fix nitrogen in the soil and thus contribute to a sustainable nutrient supply. Buckwheat suppresses weeds: its fast growth takes light and space away from them.

Cover crops do not only have advantages, though. One possible drawback is the so-called “green bridge”: if cover crops are not removed in time, they can allow pests and pathogens (e.g. aphids or fungi) to survive until the next main crop. The cover crop must also be removable mechanically to leave a clean seedbed for the following crop – good timing is essential here.

Despite these challenges, the positive effects outweigh the drawbacks for us: healthy soil structure, active soil life, better nutrient availability and a contribution to ecological balance. Cover crops are an important building block of sustainable agriculture for us.