Adequate fertilization with P base materials can have significant influence on economic yields from short-season cotton (Gossypium hirsutum L.). Rates of urea phosphate (UP) ranging from 22-90 kg P205/ha were evaluated on an alkaline Oreaia sandy clay loam (Typic Ochraqualf). Urea phosphates which included UP (17-44-0) and UUP (36-12-0, 29-29-0) were studied at varying rates of N. Diammonium phosphate (DAP) was compared with UP at selected rates. All materials were applied in preplant bands. Lint yield varied highly with seasonal precipitation and ranged from 500 to 1100 kg/ha. In seasons with higher rainfall, response to P appeared linear with a weak quadratic component. When moisture stress limited yields, plant response to P became erratic. Urea phosphate produced yields equivalent to those from DAP. Tissue P levels varied with P rate in certain seasons. Cotton fiber strength appeared to be influenced by P rate. Fiber length and micronaire were unaffected by P rate.