In the rose test The Perfect Rose, which is running at Wageningen University & Research, the crop survived the summer well. This summer had three hot periods (June 23-25, July 23-27, August 23-27). In the rose greenhouse with cooling, during those periods the 24-hour temperature could be kept lower than the outside temperature, whereby especially in the evening and night the temperature was lower than outside. The quality of Red Naomi! and Avalanche+ remained good, although the branch weight on average dropped slightly and the branch length became less than in the spring.
In the three worst weeks, the branch weight of Red Naomi! was on average 45 grams and the branch length on average 61 cm. A year ago this was 40 grams with an average of 59 cm. The quality was therefore clearly better than in 2018. In that year it was necessary to chalk the greenhouse against excessive radiation, in 2019 that was not necessary. Last spring, a third of the greenhouse was planted with new Avalanche+ plantings, which reduced the humidity. The implemented cutting strategy this spring has been focused more on quality retention.
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