The effects of climate change on the flowering of Yoshino cherry trees in Japan

02 Jan 2025
690

Climate change is transforming the seasonal cycles of plants, including key processes such as flowering. A study conducted on Hachijojima Island in Japan analyzed the behavior of the Yoshino cherry tree (Cerasus x yedoensis) at the southern limits of its distribution, collecting data from 1948 to 2024.

The aim was to understand the relationships between two crucial parameters for flowering: cold exposure, necessary for dormancy release (chilling requirement), and heat required for bud development (heat requirement). This study provides a detailed picture of the effects of global warming on the phenological cycles of this species, showing how even modest variations in seasonal temperatures can significantly delay or even prevent flowering.

The study focused on Hachijojima due to its distinctive climate, characterized by relatively mild winters and temperate springs. The first flowering date was correlated with daily average temperatures, distinguishing between cold exposure periods (<10 °C) and heat accumulation periods (≥10 °C). The results revealed that in years with warmer winters, cold exposure was insufficient, leading to significant delays in flowering, sometimes by weeks compared to the climatic norm.

A particularly noteworthy winter was 2023–2024, marked by temperatures 1.0–1.6 °C above the seasonal average. Under these conditions, the first flowering date occurred on April 15, much later than in years with colder winters. The relationship between cold exposure and heat requirement was modeled mathematically using linear and logarithmic functions, which showed a significant correlation: the greater the cold exposure, the lower the heat requirement, and the earlier the flowering.

The study highlighted two main patterns influencing the flowering date. In the first, colder winters accelerate the transition from dormancy to bud growth; if spring temperatures are warm, flowering occurs rapidly, while colder spring temperatures slow down development. In the second pattern, milder winters delay dormancy release, requiring higher spring temperatures to compensate for the delay. However, if spring temperatures remain low, the delay in flowering becomes even more pronounced.

Climate change poses a growing challenge for the Yoshino cherry tree, particularly in regions at the southern edge of its distribution. The lack of sufficiently cold days during winter could prevent flowering in the future, jeopardizing the survival of the species in these areas. This is

particularly evident considering that despite the increase in spring temperatures observed since 1948, the average flowering date has not shown significant trends, suggesting that the system is already at the limit of climatic compensation.

The findings of this research not only offer a detailed understanding of the phenomenon but also have practical implications. Understanding the dynamics of cold exposure and heat requirement can help develop more accurate predictive models for flowering, essential for managing and protecting this iconic species. Furthermore, preserving the Yoshino cherry, a symbol of Japanese spring, will require targeted adaptation strategies, such as selecting more resilient varieties or identifying favorable microclimates.

It remains essential to monitor climate change and its impact on plants. Studies like this are crucial to anticipate the ecological and social consequences of global warming and to develop solutions that can mitigate its most dramatic effects.

Source: Shin, N., Saitoh, T. M., Takasu, H., & Morimoto, H. (2024). Influence of climate change on flowering phenology of Yoshino cherry at its southern distribution limit. International Journal of Biometeorology, 1-5. https://doi.org/10.1007/s00484-024-02797-0.
Images: Planet Naturale; Forest ReLeaf

Andrea Giovannini
University of Bologna (IT)


Cherry Times - All rights reserved

What to read next

Australian season kicks off: growers are confident in the 'Victorian season' 2023

Press review

07 Sep 2023

The Victorian cherry season starts at the beginning of November and reaches good volumes by the middle of the month, continuing until after Christmas including a long festive season - a perfect match for festivals and gifts. The season lasts about 100 days.

Cherry fruit quality: from sugar content to genetics

Quality

05 Mar 2025

The study conducted by Spanish and US researchers explored the genetic factors behind key factors influencing the taste of sweet cherries, including sugar and acid content.

In evidenza

New cherry packing line completed by Washington Fruit Growers

Post-harvest​

22 May 2025

Washington Fruit Growers unveils a new cherry packing line developed with Unitec. The facility boosts production capacity and brings in advanced technology to ensure quality, flexibility, and speed in meeting the growing global market demand.

How to improve cherry quality by reducing bruises and postharvest decay

Tech management

22 May 2025

Bruising, pitting and rot affect postharvest cherry quality. Learn how container choice (totem, bucket, or capacho) and cherry variety (Santina, Sweet Heart, Regina, Lapins) influence firmness, mechanical damage and shelf-life under cold storage conditions.

Tag Popolari