A 2‐year (2001 and 2002) organic soybean [Glycine max (L.) Merr.] study evaluated the contributions of row width (narrow 8‐inch and wide 30‐inch), mechanical weed control equipment (rotary hoe and cultivator), cultivation frequency (1 to 3 passes with one or both implements), and cultivation timing (early, late, or sequential) to annual broadleaf and grass weed control and grain yield. Narrow row (NR) systems reduced the timeframe available for cultivation compared to wide rows (WR) due to quicker canopy closure. A rotary hoe (RH) was equally or less effective in controlling weeds compared to a cultivator. Weed control was similar for early or late RH treatments, and early or late cultivator treatments. Yield did not differ among treatments in 2001. In 2002, the highest yields were achieved in WR with sequential 1 RH, 2 cultivator passes (54 bu/acre) compared to NR, 1 or 2 RH treatments (27 to 33 bu/acre). WR systems provide greater flexibility in cultivation equipment and timing, and may provide greater yield stability than NR systems.

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