Xeriscape gardening is drastically gaining popularity as we face climate change that affects rainfall amounts. Over the recent years, even the lush, green gardens in the Northeast U.S. have had to endure more droughts. Xeriscaping is ideal for many garden situations, including rock gardens, rocky soil, slopes, salt spray environments, harsh winds, and bright sun.
You need to consider a number of elements when designing xeriscaped gardens, such as creating irrigation systems, grouping plants according to their water requirements, and choosing the best type of mulch.
Benefits of Mulch in Xeriscape Gardens
Mulch is simply any organic or inorganic material used to protect soil from moisture loss and/or improve the condition of soil when applied on the surface. You need mulch to help keep moisture in and weed out of your garden. Mulches come in a variety of forms, including pine back, straw, cocoa shells, mini nuggets, rock, and shredded back.
You should mulch your garden at the onset of the growing season each year. This protective layer effectively insulates the soil from the hot summer sun and dry winds while at the same time eliminating weeds.
Mulch also covers the soil, keeping it cool and reducing the evaporation of moisture. As a result, mulching reduces the water required by up to a third throughout the growing season. Soil typically stays moist under the mulch, and as organic mulch decays, it improves the soil.
Mulch also minimizes weed growth and reduces runoff and erosion. It can help maintain a more constant soil temperature by buffering the extremes, hence favoring a healthy population of earthworms and other beneficial microorganisms in the soil.
Types of Mulches
There are two main categories of mulches: inorganic, and organic. Organic mulches include straw, wood chips, peat moss, leaves, sawdust, dry manure, grass clippings, pine needles, and bark chips. Inorganic mulches mostly include rock, lava, and gravel.
After the mulch is applied, there is no need to hoe between the rows. Ensure that the mulching is at least three inches thick for it to be effective.
When to Use Inorganic Mulch
Inorganic mulches such as rock and gravel can add exciting color and textural appeal to a garden. In the dry areas of your garden, rock can provide a clean, pleasant appearance and will not blow away under high winds. For perennial gardens and rock gardens with xeric plants, consider crushed gravel mulch since it encourages most perennials to self-seed.
Penstemon, Lavender, Santolina, Flax, Cariopteris, Yuccas, Agastache, Ornamental Grasses, and several other native species also thrive in rock mulch. Rock mulches are ideal for windy situations where lightweight materials such as leaves will blow away. They are also preferred in areas bordering on wildland where wildfires can occur. The only disadvantage of rock mulch is that it reflects heat and glare, an important consideration around building entries, windows, and patios exposed to the sun.
When to Use Organic Mulch
Organic mulches have the advantage of not reflecting heat and glare, and they gradually add organic matter to the soil. They are ideal for flower beds where there is always some planting activity. Organic mulch provides coarse compost that you can dig into the soil when planting new flowers. For more permanent plants such as trees, shrubs, and groundcover, consider pine needles, screened hog fuel, or bark shells.
When using decomposing organic mulches, you should be aware of the possibility of nitrogen deficiency. As organic mulches decompose, they utilize some of the soils’ nitrogen content, triggering a deficiency. A common sign of nitrogen deficiency is a yellowing of plants, especially of the lower leaves. When this happens, apply nitrogen fertilizers to the surrounding plants.
When to Apply Mulches
If you are using mulch to control weeds or for aesthetics, be sure to spread it before the weeds begin to crop up. If the mulches are meant to protect new transplants from freezes in the fall, apply the mulch soon after transplanting. And if you intend to use the mulch to reduce frost-heave and delay spring growth for plants such as crocus and other bulbs, apply the mulch after the ground has frozen.
Ultimately, proper use of mulch can improve water-efficiency in your garden while enhancing aesthetics and keeping weeds at bay. For more information about mulching xeriscaping gardens, contact us today. We are a landscape maintenance company that specializes in maintenance, repair, irrigation, and water-saving landscape design.