Interactions of Poultry Litter, Polyethylene Mulch, and Floating Row Covers on Triploid Watermelon

Triploid watermelon ( Citrullus lanatus Thunb.) was grown on the same plots in 1990 and 1991 and fertilized with either poultry litter or commercial fertilizer. Additional treatments included bare soil or plots mulched with black polyethylene, and plots with or without spun-bonded fabric row covers over both bare soil and mulch. Watermelon yields were unaffected by fertilizer source in 1990 butwere significantly higher for poultry litter than for commercial fertilizer treatment in 1991. Polyethylene mulch significantly increased postharvest soil NO 3 and leaf N concentrations in 1990 and increased yield and yield components in both years. There were no beneficial effects of row covers on yield in either year, presumably because no early-season freezes occurred.