NPK Fertilization and Deflowering Increases Leaf Yield and Extends the Vegetative Phase of Cleome gynandra L.

Spider plant (Cleome gynandra L.) is among some of the African Leafy Vegetables whose consumption is on the increase in Kenya. Production of the vegetable is constrained by low leaf yields resulting from, among others causes, the short vegetative phase of the plant. In trying to address these problems, a study was conducted at Egerton University, Kenya, in 2014-2015 to investigate the effects of various levels (0, 100, 200, 300 and 400 kg of Nitrogen-Phosphorus-Potassium ha-1 fertilizer and deflowering and no deflowering. The experiment was a 5x2 factorial arrangement in Randomized Complete Block Design (RCBD) with 10 treatment combinations. Data collected included number of primary branches, plant height, fresh and dry leaf weight and the harvest period in weeks. Data were analyzed using analysis of variance with the SAS statistical package. Means were separated using Tukey’s Honestly Significant Difference. Results indicated that deflowering and NPK fertilization significantly (P ≤ 0.05) influenced the fresh leaf yield, dry leaf weight, number of primary branches, plant height and significantly extended the harvest period. Application of 300 kg NPK ha-1 combined with deflowering gave the highest leaf yield of 1090.32 kg ha-1 and 873.24 kg ha-1 in season 1 and 2 respectively compared to the other treatment combinations. This combination also gave the highest number of primary branches per plant and extended the harvesting period by eight weeks in both seasons compared to the control. In conclusion the application of 300 kg ha-1of NPK fertilizer and deflowering is a horticultural management solution to the low productivity of spider plant vegetable.