Frank Teuton, your two cents carry great value! However, your comments and the original post worry me somewhat: The semi-arid climate and general agricultural conditions in South Africa can be summed up as being "naturally depleting of soil organic matter" compared to the temperate climates which are more conducive to building soil organic matter. There is a move in thinking here that green manuring and "underground sheet mulching" through growing green manures, is more effective (or optimal when considering time, energy, water, benefits, etc) than making and then spreading compost.
I have found that green manuring, even mowing weeds on a regular basis and leaving the material on the surface, improves the friability of my sandy soil much faster than compost does, seems to do so at greater depth and lasts longer than the positive effects of compost, even after tillage (hand digging). Stephen Barrow
