KindHarvest summary: The 2021 heat dome pushed Washington wine-grape growers to change irrigation and canopy management as temperatures reached 113°F and 28 days exceeded 95°F. The experience showed that drought and heat responses must follow current conditions and crop stage rather than a fixed calendar.
Managing fruit exposure
Growers thinned shoots and removed leaves earlier to reduce crowding while avoiding sudden fruit exposure during peak heat. Some allowed a less manicured, more sprawling canopy to retain useful shade. The right response depended on whether an extreme event arrived early in the season or close to ripening.
Water availability changes the options
Washington growers in the report still had access to irrigation water, unlike many California farms facing restrictions and idled land. Even so, higher temperatures increased crop water demand and contributed to sunburn, poor fruit set and lower yields.
From calendar management to monitored decisions
Washington State University extension specialist Michelle Moyer argued that historical averages are becoming less reliable. Forecasts, crop stage, soil moisture and local water supply need to guide the timing of irrigation and canopy work. These practices are crop- and region-specific, so they require local validation.
Source and credit
This KindHarvest Team research brief is based on reporting by Lee Allen for Farm Progress, published 26 May 2022. The publisher has corrected the article address since KindHarvest first linked to it. Read the full Farm Progress article.