Peach floral bud cold hardiness of eleven cultivars in western Colorado

Floral bud damage due to cold is the greatest limiting factor to successful fruit production in Colorado.
Peach cultivar selection can optimize the likelihood of consistently setting fruit.
Eleven peach cultivars were repeatedly analyzed by differential thermal analysis (DTA) From November 2019 through March 2020. In early November, a significant frost event resulted in floral buds which could survive at very low temperatures.
Later in November, after warm temperatures, there was a loss in hardiness across all cultivars.
Hardiness generally increased from November through early January and then decreased gradually until March.
The cultivars ‘Redhaven’ and ‘Glohaven’ showed the highest average cold hardiness ranking across the dormant season.
An average of the LT₅₀ for the first (acclimation) and last (deacclimation) measurements can provide insight regarding which cultivars performed best at the most critical times of the year.
Based on this measure, ‘Newhaven,’ ‘Blushingstar,’ ‘Glohaven,’ and ‘Glowingstar’ were the cold hardest cultivars.
The two least hardy cultivars were ‘O’Henry’ and ‘Starfire.’ This data can help inform growers on how to select cultivars that offer the greatest chance of successful fruit production in areas with high frost damage risk.

XII International Symposium on Integrating Canopy, Rootstock and Environmental Physiology in Orchard Systems

D.G. Sterle, I.S. Minas

Prunus persica, acclimation, chill accumulation, cold damage, differential thermal analysis (DTA), dormant season, lethal temperature

https://doi.org/10.17660/ActaHortic.2022.1346.22