By Calvin Finch Ph.D., Guest Author
Mulch is an essential part of gardening in South Texas. There is a long list of benefits to the practice of mulching. Saving water leads the list. Mulch saves water by insulating the soil. Mulch also keeps the soil cool. The summer sun beating down on bare soil heats it to temperatures so high that root growth does not exist in the upper two inches of the soil. When we only have 4 to 6 inches of soil, we cannot afford to lose the top two inches. Organic mulches will usually not eliminate all weeds but they certainly reduce weed pressure and make them easier to remove.
The best mulch is the one that is the most available. We don’t know who ever started the rumor that pecan and oak leaves were not good for mulch because of acidity, but they were wrong. In highly alkaline soils like ours, the addition of a little acidity helps free nutrients.
It is a real tragedy to send leaves to the landfill with the garbage pick-up. We waste the organic material, pay to have them hauled away and then waste valuable landfill space.
City of San Antonio residents can get inexpensive brush mulch at the 1800 Bitters Road Brush collection site. Call 311 for details on cost and availability. You have to load it yourself, but the material is excellent for placement over newly-planted tree roots and in the shrub border. Three to four inches of mulch over the roots of a newly-planted tree increased growth rate by about 40% when compared to trees in which the sod grew up to the trunk.
Calvin R. Finch is a director at Texas A&M Water Conservation and Technology Center.
