Abstract

Amaranthus hybridus is a leafy vegetable consumed by rural communities in Limpopo Province of South Africa and Angola. The rural communities solely depend on nature for the supply of A. hybridus pot herb which is harvested from the wild during the rainy season. Cultivation of this leafy vegetable would greatly benefit the local communities, contribute to food security and alleviate hunger, malnutrition and poverty. The optimum NPK fertilizer requirement for A. hybridus cultivation is unknown. A greenhouse experiment was conducted to determine the optimum NPK fertilizer level required for the cultivation of A. hybridus leafy vegetable. Uniform four-week-old A. hybridus seedlings were transplanted into 20 cm diameter plastic pots containing 3: 1 pasteurised river sand and Hygromix. Six treatments, namely, 0, 2, 4, 6, 8 and 10 g NPK 2: 3: 2 (22) fertilizer rates were arranged in a randomized complete block design, with 10 replications. At harvest, plant response to NPK 2: 3: 2 (22) fertilizer rates were in a density-dependent growth patterns with applications below 10 g improving plant growth. There was a strong relationship between NPK application and plant variables with the models explained 97, 90, 97, 97 and 98% in chlorophyll content, dry root mass, dry shoot mass, plant height and stem diameter. The optimum NPK 2: 3: 2 (22) fertilizer application for A. hybridus leafy vegetable was optimized at 9.01 g/plant equivalent to 90.10 g/ha. In conclusion, the cultivation of A. hybridus requires 9.01 g/plant, which needs to be validated under open field environments.