Just as the quality of the milk and the health of the cow depends on the quality of the hay we feed, the quality of the of the crops we grow corresponds directly to the health of the soil. We are fortunate that we have tons of wonderful composted manure to put on the soil. We also use different " green manures" in the form of cover crops to enrich the soil. In the summer, we use buckwheat. We can seed it, and till it in 30 days later ( see top picture). It adds lots of organic matter to the soil. Buckwheat is very tender, so it's best used as an early summer crop.And because to grows so fast, we can get another vegetable crop on the garden, or, if we don't need the space, we can sow another cover crop( field peas are a favorite for nitrogen, or if we're looking to add lots of organic matter sudan grass is a good choice) Later in the year ( like now, mid October) we like to use oats. They grow well into the fall, and because it winter kills we are able to get on the garden with the tractor to till easier than if we used something like rye that begins growing again early in the spring. The roots hold the soil which is nice on the slope of our garden. In the 27 years we've been gardening here, the soil has really changed from a heavy clay garden to a much lighter soil , and judging from the health of our crops, the fertility is right there.
The oats in the lower picture were seeded after the tomatoes came out. What a lovely winter coat!