   Conservation Mulching - December 30, 1998 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County It's time to make good on your gardening New Year's resolutions. Let's toss out some ideas to beautify your home landscape and reduce your home garden workload. Mulch your trees and shrubs to conserve water. Start a composting program that reduces the waste going into the landfill and recycles your yard and kitchen wastes. Remove that gravel and plastic landscape and plant drought tolerant trees and shrubs. While you are at it, put in a drip irrigation system to get the new plants off to a good start. This train of thought is beginning to sound ambitious, but these ideas will save time and resources in the end. You will also have the satisfaction of knowing that you are conserving natural resources. Several ideas listed above will reduce the time spent on the gardener's least favorite activity . . . weeding. By mulching the soil surface and strategically placing drip irrigation emitters where the plants need them, we can eliminate most weeds between our trees and shrubs. Mulches prevent annual weed growth by creating a physical barrier so that weed seeds blown in will have difficulty establishing themselves. Likewise, seeds already within the soil will have difficulty penetrating upwards through the mulch. Mulch does not control perennial weeds, such as bemudagrass. These weeds should be sprayed or removed prior to applying the mulch layer. Mulch also prevents mud or rain splash on flowers and fruit (such as strawberries). Mulches can also prevent wind and water erosion of soil. Gravel in the landscape does little to moderate temperature extremes. If your mind is set on a gravel landscape, use landscape fabric rather than plastic underneath the gravel to prevent weed growth. Landscape fabric is a synthetic mulch that allows air and water exchange and conserves soil moisture by reducing evaporation losses. The fabric also lasts longer than plastic in our arid environment. Organic mulches can vary from landscape bark to chipped trimmings and woody debris to lawn clippings. These materials insulate the soil surface against temperature fluctuations. In summer, a layer of organic mulch will cool the soil making it a more hospitable environment for root growth and beneficial microorganism. During spring and fall the mulch will prevent large soil temperature fluctuations that can slow plant growth. Because of its "cushioning' effect, an organic mulch lessens soil compaction due to human foot traffic while weeding or working in flower, tree or shrub, or groundcover beds - or the vegetable garden. As they break down and decay, organic mulches also add to the soil fertility and improve soil structure. Mulches have design benefits as well. Many are aesthetically pleasing and provide visual interest through texture and color. At the same time, they function to unify a landscape planting or bed. This is especially true when the bed is first planted and the plant material is small and occupies only a small proportion of the space it will eventually use once mature. If you want to get an early start on your New Year mulching program, then take your Christmas tree to the Cottonwood Transfer Station at 1500 W. Mingus Ave. They will recycle it into chips (for a $1.00 charge if you are not a Cottonwood resident) and you can load up free organic mulch while you are there. This is an excellent way to begin the new gardening year by conserving and recycling. The University of Arizona Cooperative Extension has publications and information on composting and mulching. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 or E-mail us at mgardener@kachina.net and be sure to include your address and phone number. |