A thick layer of mulch is one of the most practical ways to conserve water in the garden. Here’s how to get the best out of mulching your garden.
We have much to learn from Australian gardeners, who with similar growing conditions and low water availability, use mulching as a standard garden practice. It is so common there, that the thin fleecy fabric that is used to keep the mulch separate from the soil is available at most supermarkets, hardware stores or garden centres, in rolls by the metre!
So what is mulch really?
This is a loose term describing coarse organic matter or inorganic material that is spread in a thick layer over the surface of the soil to conserve moisture, keep down weeds and control soil temperature.
What kind of mulch can you use in your garden?
- Organic material such as bark chips, dry lawn clippings, autumn leaves, pine needles, etc are most popularly used. Over time these decay and become incorporated into the soil, adding to the soil fertility.
- Inorganic materials such as pebbles, gravel, glass marbles, etc can also be used. The advantage of inorganic mulch is its long lasting capability.
The most readily available and cost effective mulch used in the Eastern and Southern Cape area is coarse pine bark. Wood chips (a by-product of the tree felling industry), is great as it is usually heavier than bark and takes longer to break down.
What are the real benefits of mulch?
The main aim of mulch is to conserve the soil moisture and keep the soil temperature down. All soil directly exposed to the sun will heat up tremendously, resulting in major water evaporation. A thick layer of mulch also prevents any weeds from seeding or growing. Weeds steal moisture and nutrients from your treasured plants. In addition, a layer of mulch is aesthetically pleasing and neat, and cuts down tremendously on maintenance of beds.
How to lay mulch
Prepare the area over which the mulch is to be laid. You may want to incorporate fibre palm peat, water retaining granules, compost and fertiliser into the soil. Create a dam or hollow in the soil around each plant. As water percolates through the mulch, it will collect in this depression, soaking in around the roots.
You can place a layer of material (Weedgard or landscape fabric) to separate the mulch from the soil. This will prevent the soil from contaminating the mulch or making it easier to remove the mulch should you wish to work in the soil, plant new plants or do regular maintenance. Apply a thick layer of mulch around your plants at least 1m in diameter around most trees and shrubs. Our Australian counterparts utilise mulch to the depth of 50cm, but 10-20cm should suffice.