OKLA. CITY —
As our weather gets hotter and dryer, the need for mulching increases. If you have not mulched your garden yet, now is the time to do so. Mulching is usually applied soon after the emergence of the crop seedlings or following transplanting.
Sooner is better than latter. The delay of a mulch layer may be desirable if the soil has not warmed sufficiently during the spring season. This should not be a concern during an Oklahoma June.
Mulching is putting material around your plants. Although there are nonorganic materials on the market, they are not recommended. Using organic materials as mulch has many advantages.
Also, rocks do not make the best mulch in most circumstances. Rocks absorb heat and heat the soil under them. Natural mulches from plants cool the soil under them and improve plant health. Many materials can be used as mulches including compost, composted products, peat moss, cotton seed hulls, burrs, pecan shells, chipped cedar bark, cypress bark, alfalfa hay, wheat straw and lawn clippings.
• Mulch reduces soil temperatures. When the soil gets too hot, root development ceases, slowing plant growth and reducing plant health. Mulching is plant health action.
• Mulch reduces evaporation from the soil surface. Mulching is a water conservation action. Saved water means you spend less time watering and you will have lower summer water bills.
• Mulch reduces weed growth. Not only does mulch drastically reduce the number of weeds that sprout, but the ones that do grow are spindly and easier to remove. It is estimated that mulching will reduce 70 percent of summer yard maintenance. Mulching is a labor saving action.
• Mulch adds to the ascetics of your garden. Mulching is a beautification action.
The amount of mulch used will be dictated by the material to be used. It may be one inch deep if sawdust (not recommended), peat moss, cotton seed hulls, ground corncobs or compost is used. Four to eight inches may be needed if straw, hay, corn stalks or other coarse materials are used. Some gardeners recommend applying a 2-3 inch deep layer except when using green Bermuda grass clippings.
To get the most out of your mulch you will want to match the mulch you use to the plants it will be around. Bark makes excellent mulch for trees and larger shrubs. The coarser texture of bark matches these larger plants. Mulches that come as coarse strands resist blowing. Pine bark has a round shape, especially the larger sizes. This makes it more likely to blow or float out of plant beds.
For flowers and smaller shrubs, finer mulches, such as compost, peat moss or a composted product are better to use. These materials have an appearance that looks good under flowers and they are easily worked into the soil. Using these materials adds organic matter to the soil, thus improving soil properties. Pecan shells are often used around azaleas because they help acidify the soil.
In a vegetable garden, mulch appearance is not as important. This makes such mulches as dried or green lawn clippings, aged manure or wheat straw good choices for garden use. They are less expensive but are not as attractive. A fact sheet listing mulch materials and their characteristics is available from your Oklahoma Cooperative Extension Office (fact sheet # HLA-6005).
The following workshops will be held at the OSU Extension Center, 930 N. Portland, Oklahoma City, unless otherwise specified. They are free and open to the public. Questions-call 713-1125. Third Thursday gardening: ‘Year Round Gardening’ July 17 from 6-7 p.m.