Differences in vase lives of cut hydrangea flowers harvested at different developmental stages

Two types of cut hydrangea flowers are marketed: Fresh-stage cut flowers (harvested just after the decorative sepals are completely colored before or during flowering) and antique-stage cut flowers (harvested when the decorative sepals become green and/or red after flowering). We investigated the differences in vase lives between fresh- and antique-stage cut flowers using 10 cultivars and 5 lines of hydrangea. The antique-stage cut flowers of ‘Endless Summer’, ‘Glowing Alps’, ‘Grünherz’, ‘Masja’, ‘Temari Ezo’, and line No. 2 exhibited significantly longer vase lives than their fresh-stage cut flowers. The difference in vase lives between the cut flowers of ‘Masja’ harvested at two different stages was approximately 60 days. We conducted further studies to elucidate the contribution of detailed differences in the harvest stages to differences in the vase lives using ‘Masja’ and ‘Xi’an’. Vase lives were compared among the cut flowers harvested at four different harvest stages that were divided based on flowering of florets and greening of the decorative sepals. The cut flowers of ‘Xi’an’ harvested at the decorative florets flowering- and decorative sepal greening-stages showed significantly longer vase lives than those harvested at the non-decorative floret flowering stage. The cut flowers of ‘Masja’ harvested at two harvest stages following the beginning of the decorative sepal greening stage exhibited significantly longer vase lives than those harvested at the other two harvest stages. A recutting treatment rescued the cut flowers harvested at the decorative sepal greening completed-stages that exhibited softening of the decorative sepals. This result suggested that the vase lives of cut hydrangea flowers were terminated by the disruption of water balance caused by vessel occlusion in the stem ends. In conclusion, a relatively longer vase life can be expected when cut hydrangea flowers are harvested after flowering of the decorative florets. However, we should note that cut flowers of some cultivars harvested at the decorative floret flowering stage may exhibit relatively short vase lives. Treatments that suppress vessel occlusion may be effective for lengthening the vase lives of cut hydrangea flowers.