Mulching For A Better Garden
Organic mulching enriches the soil as they decay and provide a better environment for plant growth. Soils high in organic matter are easier to till and better suited to vegetable gardening. Adding organic material makes soils more crumbly, especially clay soils that pack and crust.
Mulches help plants by gradually increasing soil fertility. An organic mulch such as straw or newspaper can be turned under the soil at the end of the season. This helps build the soil's organic matter content. Turn the mulch under as soon as the gardening season is over so it breaks down before the garden is replanted.
Most mulches also provide excellent weed control. Mulches do not prevent weed seeds from sprouting. However, weed seedling emergence is blocked by a mulch layer thick enough to exclude light. A 3-inch layer of mulch on the soil surface keeps most annual weed seedlings from coming through. See figure 5. Weeds that bread through are removed more easily from mulched soil. Hard-to-control weeds such as nutgrass and johnsongrass may come through the mulch layer but can be pulled more easily or covered by fluffing the mulch with a fork.
Many materials are available for mulching a garden. Some examples are: compost, straw, gin trash and sawdust.
* Compost is generally the best mulching material for the home garden. It is usually free of weed seeds and is inexpensive. Prepare compost from materials present in your yard. It is not necessary to purchase expensive materials for mulching. * Straw is short lived and coarse textured. More straw is needed for the same effect as compost or lawn clippings. Generally, less of the finer-textured materials is required to provide a 3-inch layer of mulch after settling. compost, however, usually requires only about 4 inches to provide a 3-inch mulch layer. * Gin trash is commonly available in Texas. It is risky to use, however, without knowing its source and prior treatment. Make sure that the farmer did not use arsenicals on the cotton. Arsenicals are long-lived chemicals that can be present in gin trash for several months or years. Also, gin trash may contain weed seeds and diseases. Compost gin trash before applying it to your garden to make it safer and easier to use. The heat generated by composting kills most weed seeds and most disease organisms that infect plants. * Sawdust is commonly available especially in East Texas. If well managed, it can be a good mulch. It can result in a temporary, but sharp, decrease in soil nitrogen. Add a small amount of garden fertilizer to the soil after applying sawdust directly to a garden. Even better, add nitrogen to sawdust, then compost it before spreading it on your garden.
Texas A&M Plant Answers