Two Dwarf × Tall hybrid coconut fertilizer experiments in north-east Zaïre are described. The first was a 25 factorial experiment, to study the effects of N, P, K, Mg and B on growth and yield of copra. The second compared four levels KCl (0, 2, 3, 6 kg tree-1 year-1) and three levels of (NH4)2SO4 (0, 2, 4, kg tree-1 year-1). In the first experiment, KCl fertilizer applied to immature palms had a significant positive effect on growth and flowering precocity, and on yield once production started. There was a significant positive effect of N on growth in the first year after planting, but not thereafter. Phosphorous, Mg and B had no significant effects on any of the parameters studied. Later, an NaCl treatment was substituted for the B treatment and there was a positive yield response. In the second experiment, the application of 2 kg KCl tree-1 year-1 to mature trees increased nut production by 30%; higher levels gave no additional response.