Effects of potassium and sulfur fertilizer types on Arabica coffee in basalt soil of Lam Dong province

Abstract

The experiments consisted of four treatments with three types of potassium and sulfur fertilizers, arranged in a randomized complete block design with three replications. These experiments were conducted in 2018 and 2019 on basalt soil for growing coffee in Da Lat City, Lam Dong province, to identify the types of potassium and sulfur fertilizer suitable for Arabica coffee in the business stage. The results show that the yield and quality of coffee depend on the types of potassium and sulfur fertilizer application. The highest yields at 15.6 tons of fresh bean/ha (2018) and 17.4 tons of fresh bean/ha (2019) were obtained with K₂SO₄ at a rate of 300 kg K₂O/ha + 60 kg S/ha. The quality of beans is also the highest with this type of fertilizer. Therefore, it is recommended to apply this fertilizer rate and a mixture of 300 kg K₂O + 60 kg S + 10 tons of decomposed chicken manure + 280 kg N + 120 kg P₂O₅ + 500 kg lime for 1 ha of Catimor coffee at the business stage to achieve the highest yield and quality.