Mulch is applied on landscape beds in early fall and late spring. My month of choice is September, as it will “tidy” up the landscape after a grueling summer and lay the foundation for a long winter’s snooze without a lot of hard work and fuss.
At its best, mulch provides nutrients — especially carbon, nature’s workhorse — to the soil. It also increases soil structure, reduces soil moisture loss, reduces soil temperatures and reduces plant competition so roots can grow quickly and farther.
Mulch is the general term for two types of products: inorganic and organic mulch.
Inorganic products include decomposed granite, small river rock, rubber pellets and black plastic. Although they reduce soil moisture loss and temperatures beneath the soil surface, they hardly provide any environmental benefits. Certainly, river rock absorbs heat during the day and creates mini-heat islands next to the house during the night. Yikes! As if we don’t have enough heat at night during July and August.
On the other hand, organic mulches such as woodchips, pine bark, pecan shell, pine needles, straw and live oak leaves provide carbon and nitrogen as well as reduce moisture loss, soil temperatures and plant competition. Conversely, they do not absorb heat during the day.
The depth of application for all mulches is 1-2 inches. Ideally, we first apply ½ inch of quality compost and then add ½ to 1 inch of mulch. This is exactly like nature does it and one can’t improve upon nature. When more than 2 inches are applied, we run the risk of watering the mulch and not the soil.
We have some of the finest purveyors of mulches — both inorganic and organic — right here in the San Antonio area. Just check out our patioscape partners.
Not only is September the beginning of football and the end of summer, but it’s also the best time to lay down a little mulch. Your landscape will thank you.
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About our expert
Mark A. Peterson is a conservation project coordinator for San Antonio Water System. With over 30 years of experience as an urban forester and arborist, Mark is probably the only person you know who actually prunes trees for fun. When not expounding on the benefits of trees and limited lawns, you’re likely to find him hiking San Antonio’s wilderness parks or expounding on the virtues of geography and history to his friends.
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