Zambia Agribusiness Society

General Production Requirements ·          Sweet potato is very sensitive to frost and cold. It requires hot days and warm nights for optimum growth, with mean monthly temperatures of 21°C to 29°C. ·          Popular varieties are Lukulu, Mulungushi, Kalungwishi, Lwangwa, Lunga, Kafue and Chingovwa. ·          Sweet potato requires 4 to 6 months to produce economic yields. ·          A well-managed sweet potato crop should yield 5 to 7.5 tons per Lima (20 to 39 tons/ha). Land Preparation/Soil Type ·          Deep, loose well drained loamy soils (does poorly on clay soils) with a pH range from 5.5 to 6.5 are ideal for sweet potato. ·          Effective rooting depth is 60cm. Deep plough field and harrow to a 60cm fine tilth seedbed. ·          Sweet potato is relatively tolerant to drought but cannot withstand waterlogging; therefore vines must be planted on 30 to 50cm ridges to avoid waterlogging. Preferred soil moisture is 60 to 75% of maximum water holding capacity.

Sweet potatoes are generally an easy crop to farm due to their low capital intensity and applicability on small tracts of land. There are two broad categories of sweet potatoes which are as follows: 1.     The staple type with white flesh and white or purple skin with a high starch and dry matter content. 2.     The desert flesh and orange skin with a high sugar and beta-carotene content. Commonly three distinct types of sweet potatoes are available for commercial production: 1.     Orange/copper skin with orange flesh e.g. Beauregard, Hernandez, Beerwah Gold, NC-3, LO-323, Centennial, Darby and Jewel. Zimbabwean orange cultivators such as Beauregard have long, cylindrical to heavy elliptic tubers. They have high beta-carotene content and are fairly quick growers. It may become too big with long growing period. 2.     White/cream skin with white/cream flesh colour, has a high yield and a good storage life. It can produce good yield in a relatively short growing period (4 months