Optimising sorghum production, Breeza 2020–21

Abstract

Key findings • Establishing sorghum at soil temperatures cooler than the commercial standard of 16–18 °C, is a viable option to move flowering and grain fill periods earlier. This helps to avoid heat and moisture stress at flowering and grain fill. • Targeting soil temperatures of greater than 12 °C for 7 days after planting, and planting into good seedbed moisture, are critical for even establishment when choosing to plant early. • In this experiment, plant establishment was close to the target population, however, soil temperatures were also warmer than normal for the first planting date (PD1; 16 September) at 16.2 °C. • Early planting results in slower crop development. PD1 was the slowest to reach 50% flowering (average 79 days) but still flowered 4–5 weeks earlier than PD3 (early December compared with early to mid January). • Early planting results in higher tillering and more fertile tillers than planting at the normal (PD3) time. • While we found plant growth differences, there was no yield effects between planting dates in this experiment.