There are very few information about fertilization of coconut grown in the State of São Paulo, Brazil. So a field experiment with 'Dwarf Green' coconut was carried out to study the effects of NPK rates on some soil chemical properties and plant nutrition, from September, 2000 to February, 2004. The trial was located on an Oxisol in the west part of the State of São Paulo (20º47'S; 51º01'W). The experimental design was an incomplete NPK factorial 1/2(4³). The treatments were annual rates of N (0, 120, 240, and 360 kg ha-1 of N), P (0, 100, 200, and 300 kg ha-1 of P2O5) and K (0, 120, 240, and 360 kg ha-1 of K2O), applied as NH4NO3, triple superphosphate and KCl, respectively. The rates of N, P e K were split during rainy season. Rates of N higher than 240 kg ha-1year-1 caused excessive soil acidification, whereas 120 kg ha-1year-1 was enough to achieve sufficiency range on leaves. Application of higher rates of P and K caused losses by leaching. It was necessary 120 kg of K2O ha-1year-1 to maintain soil exchangeable K at the same concentration as found prior to the experiment, the same rate kept leaf K concentration above sufficiency range. Foliar P contents were always higher than sufficiency range despite of P fertilization.
nitrogen; phosphorus; plant analysis; potassium; soil analysis; coconut
