Climate change effects on cherry flowering in northern Greece

Changes in phenology due to a changing environment are of interest because of their impact on fruit set, frost occurrence and final harvest. Bloom dates of sweet cherry cultivars 'Tragana Edessis' (from the local germplasm collection), 'B. Burlat', 'Larian' and 'Vogue' were examined taking climatic parameters in Naoussa (northern Greece, 40 degrees N), spanning the last 31 years (1984-2015). The annual mean temperature of 15.7 degrees C in Naoussa increased by 1.3 degrees C since 1984, confirming the hypothesis of climatic alterations during the last three decades. Cherry flowering was advanced by 5.4 days in 'Tragana Edessis', but only 2.3 days in 'B. Burlat', 1.3 days in 'Vogue' and 0.8 days in 'Larian'. This suggests a trend of more advanced flowering with later and less advanced flowering with earlier flowering cherry cultivars. This confirms results from a temperate zone cool climate cherry growing area in Klein-Altendorf, Germany exhibiting a 4-5 day advancement of flowering in the early flowering and maturing 'B. Burlat'. Due to the unique frost free climate during and after cherry flowering, sufficient chilling accumulation, and reduced cracking incidence, it appears that Imathia and its EU protected origin Rodochori-producing the cherries named 'Tragana Rodochoriou', will be able to provide many parts of Europe with cherries in June, i.e., a time when their regional fruit is not yet available.