Studies with long term storage of cut flowers of Hydrangea macrophylla
Hydrangea macrophylla subsp. macrophylla var. macrophylla has been widely cultivated as a garden and potted plant. In addition, cut flower cultivars have been developed and have been recently introduced in Chile for export to the United States. Currently, cut flowers are air-shipped in cartons with their stems placed into individual water tubes. There is little information about postharvest management. This study was conducted to explore the feasibility of exporting hydrangea cut flower stems via sea freight at the classic harvesting stage, also called antique stage. Flower stems were obtained from a commercial grower located in Central Chile. Four treatments were established: precooling (stems placed at 0.5 °C before packing), precooling + fungicide pyrimethanil or sodium bisulphite, and a non-precooled group of flowers (immediate packing). Water tubes were placed in the stem ends. The stems were packed in cartons and placed in a 0.5 °C cold room. After 20 days of storage at 0.5 °C, flower vase life was 7-9 days. In contrast, an additional experiment showed that flower stems that were stored for 35 days had a vase life of only 2 days. There was no difference in vase life between precooled and non-precooled stems. The average total water uptake per stem was 43 ml. Botrytis infection was observed only in one out of two treatments without fungicide, where incidence was 12.5%, therefore the effect of fungicides was not evaluated. It was concluded that sea shipping to the United States of hydrangea cut flowers harvested at the antique stage, would be technically feasible.