The use of biodegradable, controlled release, cellophane bags for pest and disease control and fertilizer application in watermelon (Citrullus vulgaris) in Brunei is described. The bags are made of a microperforated nitrocellulose-coated cellulose film which biodegrades completely in three to six months depending on environmental conditions and the thickness of the bag. Two trials (1979 and 1980) with seven replicates were carried out. Fertilizers and chemicals were placed in bags and buried in the middle of the plots, or they were applied in the standard way as soil dressings and sprays. A control plot had no fertilizer or chemical application. Results of the 1979 trial showed no significant differences between treatments even though control plots had a lower number of harvested fruits. In 1980 there was a significant difference between the two treatments and the control. Considerable labour costs are saved using the bags and they have a potential use in many crops.