Abstract
Improving the farming productivity and profitability of sugarcane in Indonesia requires an appropriate fertilization method. So, three types of silicate rock-based fertilizers were developed and tested in field condition. The main objectives of this research were to identify the effects of liquid-silicate rock fertilizer (LSRF) in addition to NPK, and granules of NP<sub>70</sub>-Si and NP<sub>100</sub>-Si on the growth and yield components of sugarcane grown on Udipsamments. A randomized complete block design was employed with the treatment consisting of F-0 (NPK) as the reference of fertilizer package, F-1 (NPK + LSRF applied onto the leaf), F-2 (NPK + LSRF applied to the soil), F-3 (NP<sub>70</sub>-Si), and F-4 (NP<sub>100</sub>-Si), and those were replicated in five blocks. Results reveal that the applications of those different fertilizer packages significantly affected the germination of seed buds, cane production, and sugar yield, but did not for the other growth and yield components. The order of its agronomic and economic effectiveness of the fertilizer packages, based on the value of either cane production or sugar yield, was F-2 > F-1 > F-4 > F-0 > F-3. Therefore, the use of the fertilizer package of F-2 (NPK + LSRF) may be promoted as an appropriate fertilization method to improve the farming productivity and profitability of sugarcane in Indonesia.