Fall is a good time to start a soil-improvement program for next year's vegetable garden. Plant a winter cover crop in the areas that have stopped producing. It is far better than letting the soil lie bare until spring.
Fertilize with 5-10-5 fertilizer at the rate of about 8 pounds per 100 square feet. Then spade or plow the area. Work the soil down immediately, just enough to leave a rough seedbed, and plant rye, using 2 to 3 pounds of seed per 100 square feet. Sprinkle lightly daily to hasten seed germination, and then sit back and watch it grow.
In the spring, turn the green crop under. The increased organic matter in the soil makes it easier to work, prevents soil packing and serves as a reservoir to store plant nutrients and water.
A cover crop can be grown whenever the land is not in use. You turn the rye over long before it reaches maturity, yet even when immature it helps to improve the soil.
Of considerable importance, it reduces the amount of soil lost during the winter by splash erosion and surface runoff.
Splash erosion is due to the impact of the raindrop on the soil surface. Each drop, falling as a tiny projectile, breaks small particles from the soil mass, according to University of Illinois specialists.
These particles may then be removed by surface runoff, which determines how much is actually lost. During a particularly bad winter, the loss can be much heavier than one might suppose.
Many gardeners begin to dig and plant the garden in the spring before the soil is dry enough. If soil pressed tightly in the hand does not readily crumble when released, it is too wet to be worked.
Much more organic matter could be added to the soil if the cover crop could be allowed to grow for a year. Grass plants are the best natural soil conditioners known. They produce an extensive system of small roots which thoroughly penetrate the soil.
If the garden is large enough, it can be divided into two equal parts. One part can be used for vegetables and the other half for growing a soil improvement crop. Alternate the two sections the following year and continue the procedure until the soil is in top physical condition.
This practice probably is one of the most effective and cheapest ways to improve the soil for growing almost all kinds of plants. Flowers and vegetables growing in such soil are much less susceptible to many of the diseases which might attack them.
For a nitrogren-producing cover crop, plant hairy vetch and crimson clover. Both plants have nitrogen-fixing bacteria when live in nodules on their roots. Since about 85 per cent of the nitrogen fixed by vetch and crimson clover is located in the top growth, it is important that they be planted in time for them to make good growth before cold weather.
A vetch plant that is only 3 to 4 inches high is already starting to fix atmospheric nitrogen. By the time an acre of this cover is 18 to 24 inches high next spring, the vetch will contain more than 200 pounds of nitrogen, with approximately half of it becoming available to a crop during the first season.
Vetch and crimson clover can be plowed under in the spring. Decomposing vetch and crimson-clover mulches, although located at the soil surface, appear to release their nitrogen quite rapidly to no-tillage crops.