Soil health is at the top of today’s agenda; getting it right is part of the solution to many of our environmental misdemeanours. Cover crops can provide many benefits to the soil if used appropriately.
An argument against cover crops is that they are a green bridge, a habitat for crop pests to spend the winter, before breaking out in the summer at the expense of yield in a commercial crop. To combat this threat, it is important to recognise how closely related crop species are to cover crops species. Brassica cover crops will promote club root in oilseed rape and cereals, such as rye, will harbour diseases like fusarium. Using barley screenings to bulk up a cover crop mix could increase disease levels. With the armoury in the spray shed shrinking, cultural disease control becomes more critical and the wrong choice of cover crop can cause problems.
However, we know that cover crops can provide a number of advantages to both crops and soil. For example, legumes in a mix add nitrogen and certain radishes are known to discourage parasitic nematodes, such as the potato cyst nematode. Cover crops also retain nutrients in the field. Furthermore, the action of the roots improves soil structure and helps to manage soil moisture levels. Consulting with an agronomist will allow you to assess the pros and cons of individual cover crops to suit your soils and rotations.
Although it can sometimes be hard to see a clear connection between planting cover crops and an increase in yield, there are many overall benefits that can be provided to both soils, the environment and the following years crop. Benefits may include a decrease in the amount of inorganic nitrogen used after planting a legume cover crop, a reduction in the need for herbicides and pesticides, an increase in the number of microorganisms in the soil and a reduction in the amount of soil erosion.
Further to this, we can look at scientific trials, such as the work at Salle Farms in Norfolk (published on the Wensum Alliance website), which suggests that cover crops are a good way of providing natural capital benefits in stopping diffuse pollution but there was not a consistent increase in gross margins as a result of a cover crop being in the rotation. There doesn’t seem to be a clear cut, overwhelming driver for all to plant cover crops, however as outlined above, there is the potential for several benefits to be gained. Therefore, leaving soil bare over the winter period is increasingly becoming an unattractive and less profitable option.
Currently there is approximately £100/ha available to fund cover crops through a mid-tier Countryside Stewardship Scheme. There may, in the future, be opportunities to receive further funding via water companies for the cover crops. Finally, there is likely to be benefits to unlocking natural capital.
At Brown & Co, our team of Agricultural Business Consultants will be able to help you understand what advantages and payments are available and best suit your business. To find your local office, please visit our website; https://www.brown-co.com/branches