Scientists at the University of British Columbia Okanagan are studying how sweet cherry trees protect their flower buds from winter frost, using a natural mechanism called supercooling.
Dr. Elizabeth Houghton, a graduate of the Irving K. Barber Faculty of Science, published a study in the journal Plant Biology analyzing this phenomenon. Supercooling allows the liquids within plant cells to remain in a liquid state even at subzero temperatures, preventing ice formation. However, this delicate balance can break if impurities or ice crystals intervene, leading to sudden freezing.
This process is vital for flower buds, which must survive the cold months to ensure the production of fruits in the following season.
The importance of better understanding this mechanism became clear after an exceptional cold wave hit Okanagan in January 2024, with temperatures dropping as low as -27°C (-16.6°F). The damage to fruit trees was devastating, with estimates indicating a loss of 90% of the anticipated summer crop.
Many tree species have strategies to withstand cold, but supercooling in stone fruits, like cherries, remains poorly understood.
Figure 1: Ice accommodation in overwintering sweet cherry flower buds exposed to in-field sub-zero temperatures. Photographs taken under a dissecting microscope on 24 February 2023 of a sweet cherry flower bud that was: (a) held at in-field freezing temperatures after experiencing a natural cold snap along with a digital diagram of the same flower bud to highlight regions of ice accommodation, then (b) thawed to room temperature. Credit: Plant Biology (2024). DOI: 10.1111/plb.13697
“The ability of sweet cherry trees to withstand winter frost through supercooling is fascinating. In this state, cellular liquids do not freeze despite subzero temperatures,” explains Dr. Houghton. “But we still don’t know exactly how this happens in certain plant structures. We want to dive deeper to understand how flower buds survive such extreme conditions.”
Unlike previous research, which mainly focused on peaches, this study shifts attention to cherries. Their buds contain more primordia — cellular structures that will develop into flowers and later into fruits — compared to peach buds, which contain only one.
Dr. Houghton examined various aspects of the phenomenon: from ice formation inside the buds to the freezing of outer layers, and the changes occurring within the buds as temperatures begin to rise with the arrival of spring.
One of the most critical aspects is the transition from winter to spring. As the buds grow, they gradually lose the ability to stay supercooled, becoming vulnerable to sudden cold snaps.
“Cherry buds have an extraordinary ability to protect themselves from frost in winter, but this defense weakens with spring growth,” the researcher explains. “We want to better understand how these buds endure such harsh winter temperatures. And with the uncertainty surrounding climate change and the possibility of more frequent and intense cold waves, it’s crucial to learn from these plants to develop strategies that safeguard future crops.”
Source: Phys.org
07 Mar 2025
"There are other factors besides the hours of cold weather," said Gardner, owner of Zaiger Genetics in Modesto, California, known for breeding early varieties of stone fruit, sweet cherries and apples.
09 Feb 2026
Sweet cherry nutrition management in Chile is crucial for reserve accumulation supporting spring growth. Post-harvest applications of nitrogen, potassium, calcium and micronutrients enhance photosynthesis, tree vigor, fruit set and overall fruit quality.
15 Apr 2026
A study from Universidad de Concepcion in Chile examines controlled deficit irrigation in post-harvest “Santina” cherry orchards, highlighting effects on plant physiology, yield, and soil microbiota without significant productivity losses and improving water use efficiency.
15 Apr 2026
Chile’s frozen fruit sector is expanding rapidly, with +26% in volume and +30% in value in 2024 and continued growth in 2025. Blueberries dominate exports, while cherries and raspberries gain momentum thanks to innovation, modern facilities and shifting global demand.
