Successful gardeners have a magic trick up their sleeves for coaxing lush growth, weed and pest resistance and water efficiency from the garden plot. It makes no difference whether one is growing perennial flowers, fruit trees, vegetables or a native border; the same trick works in all instances. Moreover, this trick can be learned by all, costs little or nothing, and can be employed anytime during the year. The magic trick is MULCH!
Mulch is a layer of matter thru which water can pass downward, but is slowed from evaporation upward. A 3” to 4” layer of mulch around the base of nearly any plant will help hold in moisture and discourage weed growth. The materials available for mulch range from decomposed granite to shredded newspapers, with a large variety of inorganic and organic materials in-between.
Materials chosen for use as mulch are determined by budget, availability and aesthetic preference. Organic materials such as leaves, pine needles, wood chips, and shredded newspapers are free for the gathering, will break down into compost, and eventually return some nutrients to the soil. The home composter can even remove materials from the pile before they are fully composted and too coarse to be used as planting mix. Organic mulches feed the soil, which, in turn, produces healthy plants with high yields of fruits and flowers.
When using organic mulching materials, weed the area from the trunk of the plant to the drip line. If drip irrigation is used, place emitters around plant approximately three fourths of the way from the trunk toward the drip line. Spread mulch evenly over drip irrigation, taking care to leave about 2” around the trunk of the plant clear, as mulch heaped on the trunk encourages fungal growth and rot. As mulch breaks down and becomes part of the soil, more layers can be added.
Our native decomposed granite makes an excellent ground cover and mulch. It has a neat, clean appearance, and many of our native plants thrive in it. Larger rocks or boulders also serve as efficient mulching mechanisms. Rocks are particularly useful for shrubs and trees, as the roots of the plant will burrow under the rock to find cool soil temperatures and retained moisture. While granite is spread in an even layer around the plant, rocks and boulders are placed with some consideration of the overall garden design. A thick layer of river rock, for example, may restrict downward moisture flow from rain, rather than gather it. When using granite and rock, it is a good idea to dig in a moderate amount of compost once a year. Simply scrape back the granite from around the base of the plant, work in compost and replace granite. Drip irrigation components can also be hidden from view by covering with granite.
Mulch can be applied any time during the year, so perform your mulch magic trick now, and enjoy the secret of successful gardeners everywhere.