ABSTRACT Untalan, Kent C. July 2022. Root Growth Response of Sugarcane to Water- Soluble Caleium Phosphate Application Under Previously Covered Lahar. Bachelor of Science in Agriculture. Major in Crop Science. Pampanga State Agricultural University, Magalang, Pampanga. Adviser: CARLO G. CUNANAN The study was conducted from May 2022 to July 2022 at Pabanlag, Floridablanca, Pampanga entitled "Root growth response of sugarcane to water-soluble calcium phosphate application under previously covered lahar." The experiment was laid out in a Completely Randomized Design (CRD) with three replications and four treatments. The treatments are T1 -Control, T2- Water-soluble calcium phosphate (chicken bone), T3- Water-soluble calcium phosphate (beef bone), and T4 - Mixture of chicken bone and beef bone. Based on the result, the mixture of chicken bone and beef bone greatly influence the root growth of sugarcane. The said treatment obtained a higher root area, longest root length and heaviest root biomass (dry weight). The data also revealed that none of the treatments affects the number of shoots and the data for response variable is constant. For recommendation, it is suggested to sugarcane farmers to use water-soluble calcium phosphate in propagating sugarcane cuttings and also this treatment to be used as a root growth enhancer.