THE EFFECT OF KNO3 CONCENTRATION LEVEL IN FOLIAR SPRAY APPLICATION ON THE PRODUCTIVITY OF GUAVA (Psidium guajava L.) “KRYSTAL” PLANTS

Abstract

Guava (Psidium guajava L.) is one of the most widely distributed and cultivated species of the Psidium genus (Paull, 2012). However, the productivity of “Crystal” guava is often not optimal. Along with the increasing market demand for “Crystal” guava, the implementation of intensive cultivation technology is needed to support production improvement. One of the efforts that can be applied is fertilization using KNO₃ through foliar spray application. This study aimed to determine the effect of different concentrations of KNO₃ applied through foliar spray on the productivity of “Crystal” guava plants and to identify the most effective concentration for improving fruit set. The research was conducted at PT Great Giant Pineapple Plantation Group 1, Terbanggi Besar, Central Lampung, from October 2025 to January 2026. The experiment used a single-factor Randomized Complete Block Design (RCBD) (4×4) with three replications. The treatments consisted of K0 (without KNO₃ application), K1 (0.2% KNO₃), K2 (0.4% KNO₃), and K3 (0.6% KNO₃). The results of analysis of variance showed that foliar application of 0.4% KNO₃ increased the number of bagged fruits and provided the best effect on fruit set formation in “Crystal” guava plants.