Storing cut flowers at cold temperatures maintains their quality and is used to help manage inventory and allow flowers to be more easily stocked for holidays, markets, and events. In addition, flowers can be cold-stored when unexpected warm temperatures speed up production, forcing early harvests.
A new study published in HortTechnology evaluated various methods of cold storage for cut tulips and Dutch irises to determine the best temperature and method to extend flower life.
Cut tulip and Dutch iris stems lasted longest when storing stems with the bulb attached at −0.6 °C. Leaving the bulb attached is also a simple and effective method of preserving vase life when sub-zero temperatures are not available.
To summarize the results, the best method of long-term storage of cut tulips and 'Telstar' Dutch iris was storing stems with the bulb attached at −0.6 °C, followed by at least an 8-h pulse of either floral solution to increase the ability of flowers to fully expand and maintain vase life.
Sub-zero storage temperatures are not currently used in the industry, but the adoption of -0.6°C, would increase if more species were shown to be tolerant of this temperature. Having the option to store multiple crops at the same temperature for extended periods would give growers and suppliers flexibility by allowing them to store more product for periods of high demand, when warm production temperatures result in early harvest, or when other issues may arise.
According to the author, Dr. John Dole, "Successful long-term storage of cut flowers has been a holy grail of cut flower researchers and companies for years. Sub-zero storage may provide the answer for some species.
For more information:
American Society for Horticultural Science (ASHS)