Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: THURSDAY, September 16, 1993                   TAG: 9309160035
SECTION: CURRENT                    PAGE: NRV-11   EDITION: NEW RIVER VALLEY 
SOURCE: JOE HUNNINGS
DATELINE:                                 LENGTH: Medium

PUT A WINTER COAT ON YOUR GARDEN

Notice that I didn't say put the garden to rest for the winter. No. After it has given to you all summer, it's time for you to give something back to your garden by planting a winter cover crop. What's a cover crop?

A cover crop is a temporary planting that adds organic matter to the soil and improves its physical condition. It can provide many benefits for the home vegetable garden. Besides adding organic matter without much effort on your part (or having to haul it in), a cover crop can extract nitrogen from the air and add it to the soil for next summers crop's.

A cover crop reduces losses of soluble plant nutrients through leaching. Its root systems can loosen heavy clay soils. It also provides a patch of greenery during the winter months, and the cover protects the garden from erosion.

\ Fall soil preparation: Pull up all dead and unproductive plants, and either place this residue on top of the soil to be tilled under or in the compost heap. Remove any diseased or insect-infested plant material from the garden that may shelter overwintering stages of disease and insect pests. If this plant material is left in the garden, you are leaving an inoculum of diseases and insects which will begin to reproduce the next spring and add to your pest problems.

Cleaning up also gives you the chance to add compost to the garden. Compost contains highly nutritious, decomposed plant material and beneficial organisms, and is an excellent soil builder. By spreading compost and other wastes on the soil and plowing them in, you are adding nutrients to the soil for next year's crop. The beneficial insects and microorganisms in the compost will help integrate the compost with the soil, and the added humus will improve soil structure.

Don't overlook other excellent sources of organic material available during the fall. Leaves are abundant, and neighbors will usually be glad to give away their leaves. Put some on the garden now and store some for next year's mulch. Leaves will mat if applied too heavily, and will not decompose quickly. You can help leaves break down more easily by running a lawn mower back and forth over the pile. Put the shredded leaves directly onto the garden, and till them in or compost them.

\ Planting the cover crop: Once the garden debris and additional organic matter have been added, it's time to prepare a seed bed. Till the garden lightly, or, for small spaces, loosen soil with a hard-tine rake. The cover crop can be broadcast and raked lightly with a leaf rake to cover the seed. If possible, irrigate after planting and then water every four to seven days until the crop has emerged.

Winter annual grain crops such as wheat, barley and rye can be used very successfully in the New River Valley. Seed at a rate of four ounces per 100 square feet.

A good mixture that I have used successfully for many years is a winter rye-hairy vetch combination. The rye is very hardy and adds a significant amount of organic matter to the soil. Hairy vetch is somewhat less hardy and fixes significant amounts of nitrogen. Sow these at a rate of 21 ounces of rye and seven ounces of vetch per 1,000 square foot.

Winter cover crops can be planted as early as the beginning of August, but should not be planted any later than Nov. 1. The plants should be come established before hard freezes stop their growth.

Winter cover crops can even be started where a gardener has fall crops growing. Sow the seed of the cover crop between the rows of vegetables a month or less before the vegetable harvest is expected. This way the cover crop gets a good start, but will not interfere with vegetable plant growth.

One problem with cover crops is that gardeners tend to delay tilling them in the next spring. Consequently, gardeners may get a late start in planting. The cover crop may require mowing before tilling if it has grown large enough to clog up the tines of the tiller. Turn over the cover as early in spring as the ground can be worked, and the benefits should outweigh the problems.

Another alternative is to clip the cover crop growth at planting time and use it for a mulch material for the summer garden. A scythe or weed eater can make quick work of a rye cover crop. The crop stubble is left in place to protect the soil from erosion during spring downpours and provide some weed control. One word of caution with this technique: Be sure to wait until after the rye has produced a seed head before cutting. This will eliminate any problems with regrowth of the rye.

Joe Hunnings is the Virginia Cooperative Extension Service agent for agriculture in Christiansburg. If you have questions call the Montgomery County extension office at 382-5790.