Effect of Mixed Fertilization Based of Potassium Chloride and Cow Manure on Oil Palm Fruit Bunch Production in La Mé, Southeast Côte d’Ivoire

Abstract

The combined use of mineral and organic fertilisers may reduce reliance on chemical fertilisers while supporting soil fertility and oil palm productivity. This study evaluated mixed fertilisation based on potassium chloride (KCl) and cow manure for fresh fruit bunch production in 11-year-old C1001F oil palms at La Mé, southeastern Côte d’Ivoire. Seven treatments, including unfertilised and KCl controls and different KCl-cow manure combinations, were arranged in a completely randomised One Tree Plot Design with 10 palms per treatment. The experiment lasted eight months. New leaf emergence, monthly trunk growth, fresh fruit bunch number, total bunch weight, and average bunch weight were assessed. Fertilisation treatments did not significantly affect new leaf emergence (P = 0.6101) or bunch number (P = 0.664). Monthly trunk growth differed significantly among treatments (P = 0.0101), with the highest value recorded under T4, comprising 1 kg KCl and 5 kg cow manure (4.38 ± 0.83 cm/month). Total fresh fruit bunch weight (P = 0.0014) and average bunch weight (P = 0.0011) also differed significantly. Treatment T2, comprising 3 kg KCl and 3 kg cow manure, produced the highest total bunch weight (19.24 ± 1.02 kg) and average bunch weight (12.41 ± 1.02 kg/bunch). The findings indicate that balanced mixed fertilisation with KCl and cow manure may support short-term oil palm productivity under the conditions of La Mé, although longer-term evaluation is required before broader recommendations are made.