Effect of buckwheat and silage tarps on sweetpotato between-row weed control

Abstract

Field studies were conducted on certified organic land in Lafayette and Vincennes, IN, in 2023 to determine the impact of different between-row weed control methods on weed suppression and sweetpotato yield. Between-row treatments consisted of organic buckwheat (108 kg ha-1) broadcast seeded immediately after sweetpotato transplanting followed by silage tarping from 3 wk after transplanting (WATr) through harvest, organic buckwheat (108 kg ha-1) broadcast seeded 3 WATr and terminated 7 WATr, and cultivation as a grower standard. Weed density at 6 WATr was 0, 184, and 162 plants m-2 for the silage tarping, living mulch buckwheat, and cultivation treatments, respectively. Total yield was 11,048 kg ha-1 for the living mulch buckwheat, 19,792 kg ha-1 for the cultivation, and 17,814 kg ha-1 for the tarping treatments. Tarping effectively suppressed weeds and produced sweetpotato yields comparable to cultivation, indicating the potential for use by organic growers. When buckwheat was grown between rows 3 to 7 WATr, sweetpotato yield was lower than it was with tarping and cultivation. These results suggest that researchers should be evaluating tarps for small-acreage farmers as a weed management strategy.