Testing row spacing and planting rate for fall‐planted spring canola in the southern United States

Cultivar selection, planting rate, and row spacing are key considerations when planting canola (Brassica napus L.) and vary by region. Canola offers a possible solution for producers in Texas and the broader southern region looking for a winter rotational crop, but the lack of data on region‐specific agronomic practices is a roadblock to adoption. Our objective was to identify the optimum row spacing and planting rate to achieve maximum seed and oil yield in fall‐planted spring canola in the southern United States. Replicated studies were conducted at College Station and Perry, TX during the 2017–2018 winter growing season. Treatments included three row spacings (19, 38, and 76 cm), three planting rates (1.7, 3.4, and 5.1 kg ha−1), and two cultivars (HyCLASS 930 and HyCLASS 970). HyCLASS 970 outperformed HyCLASS 930 in all yield and seed parameters except seeds pod−1 and oil content at both locations. While row spacing had no effect on yield at College Station, a 15% reduction in seed and oil yield was observed at the widest row spacing at Perry. A cultivar × planting rate interaction at Perry showed yield declining for HyCLASS 930 as planting rate increased, while HyCLASS 970 showed no response. This suggests rates as low as 1.7 kg ha−1, which is substantially lower than the rate commonly recommended (5.6 kg ha−1), can be used for fall‐planted spring canola. High yield at Perry and lack of freeze damage suggest spring canola may be a good winter rotational crop for the southern United States.