Regional Gardening Reports :: National Gardening Association

In the Garden:
Western Mountains and High Plains
July, 2010
Regional Report

Share |

Straw mulch around my tomatoes helps maintain uniform soil moisture and suppresses weed invasions.

Summer Mulching

Hot summer weather has its good and bad sides in my garden. Heat is needed for the production of the tomato crop and an abundance of zucchini. Hot weather woes bring on the spider mites and the cool season vegetables start to wane. It's a time to cope and think water conservation and maintaining uniform moisture availability to the vegetable and flower garden.

It's also time to be sure that summer mulches are in place. I've tried a variety of mulching materials from the synthetic fabrics, colored plastics, cocoa hulls, and others. My favorites are still the organic mulches including unfinished compost, clean wheat straw, shredded cedar, and even pine needles. Proper use of organic mulch can help to reduce soil moisture loss by up to 70 percent. Plus, the insulating ability of mulch helps keep the soil cooler in summer and warmer in winter.

In the tomato patch, mulches reduce rain and irrigation splash on the foliage, which helps to greatly reduce the spread of leaf diseases and discourages insect pests. For the organic gardener, cedar and redwood shavings really do discourage slugs in the garden. A proper mulch barrier makes it more difficult for disease spores of powdery mildew and rust to get to the plant foliage.

Another important reason to mulch is to suppress weed invasions, particularly the annual weeds like spurge, barnyard grass, foxtail, and purslane. I try to apply at least a two-inch layer of straw or dried grass clippings around tomatoes to choke out weed seedlings and prevent them from seeing the light of day. If some weeds do, by chance, get through the mulch layer, they are easier to pull out from the mulch layers.

If you're like me and have access to the many pine needles that shed in late summer and fall, collect them and use as mulch. Though there is a concern that these can be a fire hazard, use common sense in placing them around your plants and combine them with some compost. Pine needles from Austrian, Scotch, and Ponderosa pines are great as they knit together and are more wind resistant than bark chips. The concern that pine needles cause the soil to become acid is a myth, It takes many years of heavy accumulations of pine needles to break down and even appreciably change the soil pH. As the needles decompose and turn into a crumbly organic material, feel free to work it back into the soil to enhance soil structure and retain soil moisture.

The leaves in your landscape are perhaps the least expensive mulch, but they can come with some disadvantages. Some leaves are difficult to apply evenly; for example, cottonwood and other waxy leaves mat together and take years to decompose. Shredding leaves before using them as mulch is helpful and will expedite their decomposition for soil conditioning later on.

As organic mulches breakdown and decay, they form a rich, dark organic soil amendment called humus. This eventually releases nutrients, enhances the ability for micronutrients to be released, and improves soil structure.

Summer is the season of mulching. The idea is to apply a protective layer around plants to reduce evaporation, prevent erosion, maintain even soil temperatures, reduce the invasion of weeds, and in the case of organic mulches, enrich the soil.

Care to share your gardening thoughts, insights, triumphs, or disappointments with your fellow gardening enthusiasts? Join the lively discussions on our FaceBook page and receive free daily tips!


Today's site banner is by rocklady and is called "Fall is in the Air"