Organic mulches can help keep your vegetables producing during Louisiana’s hot summer months. Although mulch is usually applied to control weeds and conserve moisture, it has several other useful functions, according to LSU AgCenter horticulturist Dr. Tom Koske.
Organic mulch can reduce or increase soil temperature, reduce fruit rot and improve soil crusting problems. At the end of the season, it can be turned under to increase the organic matter of the soil.
To accomplish these ends, Koske says a mulch should be several inches thick depending on the material. Coarse, stringy mulches like pine needles will need to be applied thicker. Use only an organic material, not black plastic.
A light-colored mulch has an advantage over a dark-colored mulch at this point in the growing season. Light mulches reflect more of the sun's heat and will keep the soil cooler. A very light or bright mulch such as aluminum foil or white paint may create a problem, however, by reflecting so much light that the underside of the plants becomes sunburned.
Many types of materials can be used as organic mulch: dried lawn clippings, leaves, sawdust, bagasse, compost, pine straw and newspaper. Koske advises, however, to exercise caution in using some of these materials. For example, clippings from lawns treated with herbicides should not be used for mulch until after about the third mowing. Clippings also should be dried and dead so that grass will not reroot in the garden.
If sawdust is used, it should be well rotted. If not well rotted, apply about ¾ pound ammonium nitrate fertilizer per bushel of sawdust to supply the nitrogen that will be drawn from the garden soil in the sawdust decomposition.
When using newspaper as mulch, consider a way of anchoring down the newspapers so they won't blow into your neighbor's yard as they dry.
Mulches make gardening easier and most productive; use them and you will be hooked, Koske says.
On the Internet: LSU AgCenter: www.lsuagcenter.com/
Source: Tom Koske (225) 578-2222, or email@example.com
The LSU AgCenter and the LSU College of Agriculture