Most of us in the bay area are familiar with the term ‘clay soil’ because we all have it! For those who want to improve soil quality with very little effort, I encourage you to try a cover crop or ‘green manure’ which will revitalize the soil, suppress weeds, and help control pests and disease.
Other key advantages to cover crops are that they help to retain the soil, lessen erosion, and decrease the effect of heavy precipitation on the garden by slowing the runoff of water. The cover crop’s root system also provides organic matter and opens passageways that help improve air and water movement in the soil.
You can plant cover crops throughout the year, even up to a few weeks before frost sets in. They are fairly easy to maintain, for most you can just mow them down just prior to flowering or when the seed heads emerge on grains. All you have to do is take a mower or a weed trimmer and till the stems into the soil which will eventually decompose. Wait 2-3 weeks before planting vegetables or flowers in order to have the best quality soil!
If cover cropping sounds like something that interests you, here are some popular cover crops to choose from. We found these seeds sold by the teaspoon at Common Ground in Palo Alto:
|· Alfalfa- Deep-rooted perennial for long-term use. Plant fall or spring. Fixes Nitrogen. Takes drought.|
|· Buckwheat- Great summer compost crop. Very fast growing. Doesn’t fix nitrogen. Full sun.|
|· Crimson Clover- Annual, usually planted in fall. 6-30″. Brilliant red flowers. Part shade ok. Fixes nitrogen.|
|· Mustard- Yellow-flowered plant opens heavy soil, attracts beneficial insects. Plant in fall or spring.|
|· Fava Beans- * Edible crop; compost crop * 2-4′ annual bean. Fall. Frost resistant.|
By the way, Nitrogen fixing is a process through which atmospheric nitrogen is converted into compounds which are usable by plants. In case you are wondering, this is a good thing!