Abstract

The  research aimed to obtain the best combination of NPK fertilizer dose and foliar application frequency for increasing the yield of citrus. The research was conducted from June 2019 to April 2020 at the Ex-farm belongs to Faculty of Agriculture, Jenderal Soedirman University. The research used  Randomized Completely Block Design (RCBD) with two factors. The first factor was the NPK fertilization doses : 0, 25, 50 and 75 g/tree, the second one was frequency of foliar application : 0, 2, 4 and 6 times. The results showed that the combination of NPK fertilizer 75 g/tree  and frequency of foliar application  6 times gave  the highest number of flowers, fruitset, number of fruits, and weight per fruit.  NPK fertilization of 75 g/tree  gave  the highest number of fruit bunches, fruit diameter, and  the lowest  fruit drop. Foliar application of  six times  increased  the number of fruit bunches and the diameter of the fruit compared to control.

Keywords: Citrus, yield, NPK fertilization doses, frequency of foliar application