Climate experts warn against almond trees blooming too early

by Lorraine Williamson
almond blossom

Due to the warm winters, the almond blossom can be admired earlier in the year in Spain. That is not good, say climate experts, because it harms both the quality and quantity of the almond harvest. 

In recent decades, the almond trees have bloomed earlier each year, sometimes even a month earlier than usual. For those in the know, the reason for this is clear; it is due to climate change that disrupts the natural process in the trees and that can have disastrous consequences. 

5 times almost a month early 

The almond tree, official name Prunus dulcis, traditionally heralds spring in Spain. This is due to it being one of the first tree species to flower. But if the almond blossom signifies the beginning of spring, it already started in Spain on January 29 this year. This was when the first blossom was spotted. According to the natural calendar, that’s 9 days early. Despite storm Filomena, that was 11 days early last year. In the period between 1981 and 2022, the time of the first blossom is increasingly earlier in the year. Moreover, in the past 12 years, it even happened 5 years that the almond trees were in bloom 22 days too early. 

Furthermore, in general, almond trees bloom first in the south and east of Spain. On the Balearic Islands and along the Spanish east coast, the blossom should be visible between mid and late January, on the southern plateau mid-February, and in northern Spain only from March. 

JammFM Radio

The start of flowering depends on the temperature and the position of the sun. In October, the pores close to protect themselves against winter and the tree is dormant. For a good development of the almonds, the tree has to endure a temperature of a maximum of 7 degrees between 100 and 500 hours. For the normal hormonal course of the tree, the temperature may only rise after that so that the fruits can grow to their maximum quality. 

Not just almond tree 

Due to global warming, the winters in Spain are often spring-like: of the past 6 winters, only 1 has been really cold, 3 winters were warm and 1 winter was even extremely warm. As a result of this temperature change, the almond tree adjusts its hormonal pattern. This does not only happen with the almond tree, olive trees also adapt their rhythm to climate change. In the past 20 years, the natural rhythm of this tree species has been pushed forward by 20 days. Also outside Spain, the biological clocks of many tree species are disrupted. In Japan, for example, last year the cherry trees bloomed the earliest of the past 1,200 years. 

Quality matters 

Spain is the largest almond producer in the EU with more than 718 thousand hectares of almond cultivation, mainly in Andalucia, Castile-La Mancha, Aragon, and Catalonia. It is therefore of great economic importance that the quality of the nuts remains good. There is a fear that crops will be lost due to delayed frosts, which can sometimes occur as late as May. To prevent this, genetic research is being carried out to develop trees that flower later and are better able to adapt to the changed climatic conditions. 

You may also like