Variable weather patterns paired with increasing farm size have prompted soybean growers to explore new strategies such as early planting to minimize delays and subsequent yield loss. Field experiments were conducted in 2022 and 2023 to evaluate the effectiveness and crop safety of commonly used PRE herbicides and the effects of soybean row width on weed suppression and soybean yield in soybeans planted earlier than the current standard. Planting soybeans in early to mid-April slowed crop emergence and heavy precipitation created an environment favorable for reduced stands and PRE herbicide injury compared with those planted at a normal time. However, PRE herbicides controlled susceptible weed species when sufficient rainfall occurred for incorporation in both early and normal planted soybeans. Soybean establishment and yield were only lower in early planted soybeans when heavy precipitation resulted in soil surface crusting and high amounts of crop injury. The effects of soil crusting on stand were most evident when soybeans were planted in 19 cm row widths compared to 38 and 76 cm. Soybeans drilled in 19 cm row widths were superior to 38 and 76 cm for weed suppression at the time of POST. However, season-long weed suppression was only observed when 19 cm rows were planted at 494,000 seeds ha-1. Similarly, higher soybean yield occurred only when 19 cm rows were planted at 494,000 seed ha-1. Regardless of planting date, a complete PRE followed by POST weed management program was beneficial for weed control and soybean yield. Planting soybeans in early to mid-April will allow growers to reduce planting delays, without affecting soybean yield assuming weather conditions are not exceptionally poor during initial soybean establishment.
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