Yields of Strawberry Plants over 20 Years in Subtropical Queensland, Australia

Abstract

Productivity has a strong effect on the net returns of strawberry production. Returns are higher with high yields than with low yields, with productivity dependent on the cultivar, season and growing system. The main objective of this study was to determine the relationship between productivity and the time of planting and the time of the last harvest in Queensland, Australia. Information was collated on the yields of strawberry plants growing in this area over 20 years. Cultivars from Australia, Florida and California were planted from 2004 to 2024 and data collected on marketable yield (n = 41 cases). The transplants were planted from 16 March to 5 May, with the last harvest ranging from 6 August to 28 October. The fruit were harvested each week until they became small or soft or otherwise non-marketable. Mean yield (±standard deviation or s.d.) was 652 ± 327 g/plant, the median was 675 g/plant, and the range was from 142 to 1123 g/plant. There was a moderate linear relationship between yield and the time of the last harvest (p < 0.001, R2 = 0.43). In other words, yields increased as harvesting was prolonged. There was a positive linear relationship between yield and the length of the growing season, which included the time of planting (p < 0.001, R2 = 0.58). Yields increased as the length of the growing season increased from 108 to 205 days. These results suggest that early plantings (about mid-March for most cultivars) and a long growing season are associated with high yields in Queensland. Warm weather and intermittent rain impact fruit quality and end the harvest in this area. Yields are expected to decrease in the future under global warming in the absence of mitigating strategies.