Mulching is very important for soil and water retention but is often overlooked by farmers, so let’s recap some of the benefits.
Raindrops hitting hard soil will shatter, but a mulch blanket absorbs falling raindrops. This increases infiltration, because the rainwater can percolate, or move slowly into and through the soil.
Without mulch, the impact of the raindrops ‘seals’ the surface, causing water to run off the land and take soil with it at the same time. Mulch insulates the soil, reducing evaporation during the day and keeping it warm at night. The best and most convenient mulch in the land is the residue from the previous crop. This is why it makes sense to rotate crops such as maize and beans. Rotations also help prevent disease and pest build-up.
The minimum amount of mulch cover needed is about 30% of the soil surface area, but the greater the area covered, the better.
By keeping your land weed-free and mulched during winter, you are supporting the water table. In the first year or
two of farming, it is likely you’ll need to bring in mulch.
If grass clippings are used as a mulch, make sure they don’t have seed, which will add to your weed problem. Lay the mulch down across the slope as this helps reduce surface water run-off. Leave small gaps in the mulch around each hole, so that plants are in direct sunlight when they germinate. A huge part of the benefit of conservation farming is in the mulching, yet many farmers don’t go to the trouble of finding extra mulch and are content to just ‘dig the holes’.