Never leave your garden barren. As soon as you have finished harvesting the vegetables or flowers, plant another crop to prevent the soil from eroding or losing nutrients through leaching.
Soil devoid of vegetation is easily washed away and may find its way into the Bay. Plant roots save the soil by binding particles so they will not be washed away. The tops of plants minimize the impact of water droplets that can destroy soil structure and encourage erosion.
Creeping Charlie B-Gone
Q: Over the past few years, ground ivy has practically taken over my yard. The spores or seeds have reproduced in every crack in my walkway and around my flowerbeds. Is it possible to control it or get rid of it?
The roots of actively growing plants also absorb nutrients that were not needed for growing the crop you initially planted and fertilized. Thus, a cover crop of winter rye, wheat, oats, vetch, alfalfa, crimson clover or subterranean clover uses up nutrients, both left over and released from the decomposition of the soil’s organic matter, which continues until soil temperatures drop below 40 degrees.
Cover crops contribute to soil productivity in many ways. When plowed or rototilled in the spring, cover crops decompose, releasing nutrients slowly into the soil to feed new crops. The organic residue, primarily from the roots, will replenish the organic loss from plowing, rototilling and cultivating and from natural weathering.
Cover crops containing vetch, alfalfa, crimson clover or subterranean clover also add more nitrogen to your soil. Because these are legume crops, they are capable of fixing atmospheric nitrogen and making it available in the soil at the rate of 100 to 150 pounds per year. In many instances, this is sufficient nitrogen to grow a crop with no additional nitrogen fertilizer. Nitrogen is the most expensive nutrient in the fertilizer bag.
Cover crops of winter rye, wheat or oats absorb nutrients available only in the soil. Winter rye is a good choice because its seeds will germinate on relatively cool soils. It also has been reported as the best scavenger crop for available nutrients. To maximize benefits, farmers often sow a combination of winter rye and vetch.
Home gardeners have complained they have problems with rototilling cover crops in the spring. That problem has two solutions. In fall, don’t overseed the cover crop. If you sow too heavily, you create a turf. I limit my seeding rate to approximately six pounds per 1,000 square feet. In spring, mow the cover crop before tilling under.