When used properly mulch is one of the best natural ways to foster the growth of soil organisms and limit damage to plants from extremes of temperature in the soil as well as control weeds and break down into additional organic 'food' for the soil organisms kept so healthy by the stable temperature and slow moisture loss provided by the mulch. Mulch is really practically any organic matter laid on top of soil as a top layer. Usually at least a couple of inches thick. One problem with mulching can be the difficulty some experience in obtaining sufficient mulch. Mulch is of course for sale at co ops and nurseries but if you need to avoid spending money (as many of the community projects where Positive Cycle provide material assistance and training do) then organic material available on the land will need to be used. It may seem impossible to find enough mulch to create a blanket several inches thick covering your entire growing area but take a closer look and where organic material is in short supply Positive Cycle will place a substantial wager that there is someone nearby who burns organic material. In a misguided attempt to 'clean up' a great deal of extremely valuable organic material is wasted. (It is worth noting that ash from fires is also a valued soil additive but that is for another blog post.)
Maintaining the disciplines of vermiculture, anaerobic fermentation and also simple aerobic composting will assist you to create rich soil with more than ample supplies of dried leaves and other plant matter to use as mulch. Particularly as a barrier against moisture loss in this one of the water poor countries, mulch is a valuable lesson worth applying, whether you are a market gardener in a hot and dusty township or a hobbyist in the well watered greenery of northern Johannesburg.