Cover Crops

The following is excerpts from an email conversation concerning cover crops for a local organic farm. I am finding it very useful as this particular aspect of sustainable farming is difficult for me to understand.

Your first attempt at planning a cover crop mixture is very good. As I recall some of the resource concerns included armor (surface residue), crop diversity, soil aggregates, nutrient cycling, and infiltration to name a few. I see the mixture consists of cool season broadleaves and cool season grass, which is what we would use here for a fall seeding after harvest. The high carbon portion appears a little high, with the first 4 species making up 50%, while the legume may be a little low at 30% of the mix. I would suggest decreasing the high carbon to 40% and increasing the legume to 40%. Possibly an additional legume could be added, such as Lentil. The brassica portion at 20% looks good, since they are nitrogen scavenging and low carbon you do not need very much. The high carbon will give you soil armor and their roots will improve the soil aggregates and soil organic matter. The legumes will improve the nutrient cycling, while the brassicas create streets and avenues for the water to move into the soil profile. Improving soil health is about restoring balance, and the cover crop mixtures will help you with this task. Always try to include crop types in the cover crop mixture that are not used in the annual crop rotation, this will improve crop diversity and help feed the soil biology a more balanced diet.

I attached two cover crop pictures too.


[The photo above depicts] a 14-way mixture, which is primarily cool season. It was seeded at the Menoken Farm on May 12 and includes: wheat, oat, forage pea, lentil, ac greenfix, turnip, radish, sunflower, Italian rye grass, hairy vetch, sweet clover, phacelia, canola, and flax. The native pollinators did very well with this mixture too.


[This photo is] a primarily warm season 11-way mixture, and was seeded on June 14th at the Black Leg Ranch. It consists of: pearl millet, proso millet, sudan, soybean, cowpea, sunflower, radish, turnip, sweet clover, canola, and corn. Both are based on the clients resource concerns and objectives. This is not the first time that nature has seen this many different plants together. We have to understand they are working together and not competing. Thank you for your interest in soil health.


I have used this email without permission from it's author but thank him nonetheless.