The test results of 100 soil samples taken within 0-30 cm soil layer indicated that the soil in
Guanxi pomelo garden has
higher acidity and lower organic matter, but its contents of the available N, P, K are abundant. The soil samples which contents of available N, P, K, exceed 120 mg · kg-1, 30 mg · kg-1 and 100 mg · kg-1 accounted for 42% > 77% and 57% respectively. Most soil samples possess medium and rich contents levels of the calcium and magnesium and micronutrients. Except zinc, most nutrient contents of 100-leaf samples were or higher than optimum level, samples which contents of Mg, Fe and B were overmuch level accounted for 66%, 46% and 75% of the total. The fixed-site trials in field showed that yield of pomelo of the
balanced fertilization increased by 15.4% than that of traditional fertilization. Meanwhile the percent of splitted pomelo decreaded by 53% of balanced fertilization. The trials results indicated that reasonable proportion and application of N, K and Ca might obviously decreased the splitted pomelo percent. Under the production level of 30-40 kg per tree, the optimum N application was 0. 9 kg per tree, and nutrients proportion was N: P2O5: K2O : CaO : MgO = 1: 0. 5 : 1 : 1.1: 0. 4. Therefore, the principle of balanced fertilization should be carried out.