The Zimbabwean Gardener Issue 12 Autumn 2015 High res | Page 29

Soils which is derived from recently deposited organic matter (within 2 years): 1. 2. 3. 4. It is susceptible to microbial action. It is an energy supply for micro-organisms. It contributes nitrogen, phosphorus and sulphur. It is useful for improving drainage and aeration of heavy clays soils and reducing the capping behaviour of some soils. 5. It is vital for the overall health of the soil ecosystem! 6. It can improve soil structure. How do we modify soils in Zimbabwe? All soils in Zimbabwe will benefit from having organic matter added. This can take the form of compost/manure, mulch or a green manure crop. Green manure is simply a crop such as maize, lucerne or sun hemp that is cut before it flowers and then chopped into the soil. In winter, wheat or oats can be used. If using maize, sow at approximately double the normal density and cut before it tassels. What chemical properties are important? The acidity of a soil, measured by its pH, is important for the availability of certain elements to the plant. Extended use of chemical fertilisers will make the soil acidic, and can cause certain elements to become toxic and others deficient. It’s a good idea to lime the garden once every two to three years if living where the water supply is neutral to acid. This may not be the case where the water is alkaline, e.g. from the Chinhoyi aquifer which can cause iron deficiencies. If in doubt, get your soil analysed. Emerald seedlings We offer a wide range of vegetable seedlings. Emerald Seedlings Alpes Rd, Teviotdale Vegetable seedlings office 0772 326 446 [email protected] 29