Cover crops are commonly used to help improve the quality of a garden and improve various vital aspects of it. Gardeners use cover crops to help reduce soil erosion, improve the soil quality, reduce the amount of pests and diseases, and add additional biodiversity. These crops can be very beneficial if planted properly and can dramatically improve the quality of your garden.
If I were to choose a cover crop, I would choose Buckwheat as my cover crop. This crop is said to be very easy to work with because the roots are extremely brittle, which make them really easy to chop up with a hoe. A good, thin trap crop can be very attractive to beneficial insects. It is also organic and can grow very quickly extremely fast, which makes it more beneficial to plant in comparison to other cover crops. The residue from Buckwheat also decomposes quickly, which provides beneficial nutrients such as phosphorus for the next crops. We should use this cover crop in the orchard during the summer because it can attract beneficial insects which could help various fruit trees immensely.
(Scott, Judy. Buckwheat a Good Summer Cover Crop for Home Gardens. http://www.oregonstate.edu)