California Chill Report: Starting the 2023-2024 Dormant Period

Brian German Chill Hour Report, News from our Sponsors

Warmer winters

Starting off with another campaign this year, growers are reminded about the importance of chill hours and chill accumulation. Depending on how the winter months go will determine how well trees will wake up from dormancy, which will have a significant influence on bud break. Director of Sales for Alzchem, John Meyer highlighted some tools that are available to growers to help trees with emergence in the spring.

“We received CDPR approval for Dormex applications on walnuts. We help continue to support Katherine Jarvis-Shean and her walnut research up at UC Davis. She has some great results to share,” Meyer noted. “We also continued our multi-year trials on pistachios and again we have phenomenal results. We increased yields again in our trials even in an ‘on’ year. The whole key is timing; when to apply the application….you want to watch your chill portions. You want to maximize your natural chill as much as possible.”

Throughout the dormant season we’ll be providing updates on how chill accumulation is going throughout the state. Information from the UC Davis Chill Calculator shows that as of December 5, the Durham CIMIS station has logged 18.2 portions under the dynamic model, with 317 hours below 45°F. The station in Manteca has registered 15.9 portions, with 263 hours. There have been 400 hours in Merced, with 14.5 cumulative portions. In Five Points, there have been 293 chill hours, equating to 12.9 portions. Finally, the CIMIS station in Shafter has registered 12.7 portions, with 275 hours.

Listen to the latest chill report below.