The aim of this research is to determine the effect of giving rock phosphate and get the best dose for sweet corn production on peatlands. This research was conducted experimentally by using Completely Randomized Design (CRD) with 6 treatments and 4 replications to obtain 24 experimental units. The treatments of this research ware dose of rock phosphate 0 kg/ha, 100 kg/ha, 200 kg/ha, 300 kg/ha,…