Between May 1 and July 31, the accumulated chilling hours (CH) are counted; each variety of cherry tree requires a different amount of CH and its fulfillment is of great importance, since it is directly related to the use of the reserves that the trees have to start the following season in favor of the productive objective of achieving its potential in terms of quantity, quality and condition of the fruit.
In this context we spoke with Patricio González, an agroclimatologist from the University of Talca.
«As you know, the cherry tree requires a high number of hours of cold during dormancy, that is, during the winter, which range from 600 to 1,200 hours of cold in some varieties.
If the chilling hours requirements are not met, flowering declines, little fruit set occurs and
production declines. Cherry trees ripen from late spring to early summer.
What has happened to the hours of cold this winter? We have had 600 hours of cold
Until July 31, compared to 2022 we had had 800 hours of cold, so in this
At the moment we have a deficit of 200 hours of cold," the specialist explained.
Why have fewer cold hours been recorded this season compared to last year?
"Because of a phenomenon, which you have surely heard of, which is the El Niño phenomenon, which is a warming of the Pacific Ocean, a warming that is somehow transmitted to the continent.
Minimum temperatures have been 1 to 1.5 degrees above average. Last year
There was a cold girl event, in which the temperatures were colder, hence the
"This winter's temperatures have been relatively warmer," said González.
Producers are already thinking about dormancy-breaking strategies and/or cyanamide applications, in order to achieve different scenarios: advance flowering, homogenize harvest, etc. Of course, this year with a different scenario, without rushing, but taking into account what is coming during the next months.
«As the El Niño event will continue from the ocean to the continent, we expect that during August there will be between 150 to 200 hours or more of cold hours, so we have to be attentive to what happens during the month of August, since from spring to summer the ripening occurs, so the advice is to be attentive to the accumulation of cold hours which, unfortunately due to the effect of the El Niño event, this year have been a little lower by 200 hours compared to last year and we hope that during August something can pick up», concluded the Agroclimatologist from UTalca, Patricio González.
