Mulch is one of the best ways to protect plants from both the extreme heat and heavy downpours experienced across the country this summer.
Mulch is a loose layer placed on top of the soil and often is shredded bark, leaves, straw or pine needles. A layer of organic mulch around plantings can benefit in several ways.
In extreme heat and drought, mulch is key in retaining moisture in the soil. When the plants are watered, often restricted to one or two days a week in droughts, the texture of the mulch slows down runoff, allowing more of the precious water to stay near plant roots.
If soaker hoses are used, a light coating of mulch can protect the hose from sunlight, extending the life of the product. Most importantly, a layer of organic mulch acts as a protective blanket that holds moisture in the soil, stops the soil from forming a dry crust and helps to keep the soil cooler.
Mulch also suppresses weeds, whose roots compete with those of desirable plants for any moisture in the soil. In many ways, mulch is among a gardener's best defenses against drought.
When the rains do come in summer, they often arrive as a downpour. If intense rain hits bare, dry clay soil, the ground may shed the water instead of absorbing the moisture. Mulch helps protect the garden by preventing the formation of a crust on top of the soil during dry spells. During summer thunderstorms, mulch provides a protective layer that softens the impact of rain, slows down runoff and lessens erosion.
Mulch also stops soil from splashing onto the plants, which not only can look unattractive, but spread soil-borne diseases. With sandy soil, a slower percolation rate helped by mulch means more water reaches plant roots.
An organic mulch, such as shredded bark, has long-term benefits of adding texture and organic matter to the soil as it breaks down, increasing the water absorbing capacity of the soil over time. Mulch should be replenished at least once a year, as a rule to a depth of two to four inches.
Stone mulches should be used with extreme caution, as they can absorb heat in the summer. Long-term use of stone mulches can be difficult in most home landscapes, as leaves and plant debris can mix into the mulch and break down, changing the appearance. Stones also tend to sink into the soil below unless a barrier is used under the stone. Stone mulch may work well for some courtyards and driveways, but organic mulches such as shredded bark and leaves are recommended for most home landscape situations.
Mulches have many year-round benefits. Mulch can work as a unifying design feature, tying plant beds together and contrasting with lawns and hardscape to define areas.
An organic mulch, such as shredded bark, has long-term benefits of adding texture and organic matter to the soil as it breaks down, increasing the water absorbing capacity of the soil over time. Mulch should be replenished at least once a year, as a rule to a depth of 2 to 4 inches. Keep mulch several inches away from plant stems and trunks to discourage pest and disease problems.