Summerland Ornamental Gardens | Xeriscape

USE OF MULCHES
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The use of mulches is key to successful xeriscaping. Mulches cover the soil, keeping it cool and minimizing the evaporation of soil moisture. Mulches also reduce weed growth , help the soil capture precipitation, reduce runoff and erosion. Mulches help maintain a more constant soil temperature, buffering the extremes, thus favoring healthy populations of earthworms and other beneficial life in the soil. There are a range of mulches: Inorganic, organic and cover-crops.

Inorganic mulches

Inorganic mulches, rock and gravels can add colour and textural interest to the ground. In the dry zones of the garden, rock can give a clean, tidy appearance. For rock gardens and perennial gardens using xeric plants, crushed gravel is the mulch of choice since it encourages many perennials to self seed. Lavender, Santolina, Flax, Penstemon, Cariopteris, Agastache, Yuccas, and Ornamental Grasses, along with many native species, thrive in a rock mulch. Rock mulches are suitable for very windy situations where lighter materials will blow away. Also, in areas bordering on wild land where grass fires can occur, rock mulch can be used adjacent to outbuildings etc. as a barrier to fire. The disadvantage of rock is that it produces reflected heat and glare, an important consideration around patios, building entries & windows exposed to the sun.

Organic Mulches

Organic mulches come in a variety of forms. They have the advantage not reflecting heat and glare and of gradually adding organic matter to the soil. For flower beds where there is always planting activity the best mulch is a coarse compost that can be dug into the soil when planting new plants. For more permanent plantings such as trees shrubs and groundcover, suitable mulches are: pine needles, bark chips or screened hog fuel.

Cover Crops

Cover crops are useful in maintaining a ground cover temporarily in areas scheduled for landscaping at a later date. Cover crops keep dust down, prevent erosion and, underground, their root growth keeps the soil loose and aerated. Legume cover crops such as Alfalfa have the added advantage of improving fertility by adding nitrogen to the soil. Some other cover crops are Winter Rye and Perennial Rye. These can be dug in or rototilled when you are ready to plant. Annual vegetable crops such as potatoes, pumpkin and squash are also effective.