US: Cut flowers fare better after quick transport, despite exposure to higher temperatures

A current hot topic in the floral industry is the lack of cold temperature management (cold-chain) during flower transport. Many farms and floral internet businesses use rapid delivery companies to deliver flowers to their customers. Though timely, the delivery methods often lack proper temperature control, thus exposing fragile flowers to high or fluctuating temperatures. High temperatures during transport or storage reduce flowers' vase life and quality and make some species more susceptible to ethylene, causing rapid wilting of petals and speeding up leaf drop.

A study from researchers from the Department of Environmental Horticulture at the University of Florida, published in HortTechnology, evaluated the effect of three commercial transport systems on postharvest quality and vase life of cut alstroemeria, carnation, gerbera, and rose. Ria Leonard, Amy Alexander, and Terril Nell studied flowers transported from farms in Columbia to the US using a 7-day conventional distribution system with temperature controls and two rapid transport systems (3-day or 24-hour) with little or no temperature controls, respectively.

The researchers found that the transport systems exposed flowers to fluctuating and sometimes substantially higher temperatures than are recommended by the floral industry. Their results also showed that flowers transported using the rapid transport systems had a significantly longer vase life compared with the 7-day transport in 83% of the shipments of alstroemeria and roses, in 58% of the shipments of carnations, and in 50% of the shipments of gerberas.

"For the majority of shipments, the flowers transported within 24 hours to 3 days had increased vase life compared with those transported for 7 days," noted author Ria Leonard. "The flower species used in our study were able to tolerate high and fluctuating temperatures for short periods without substantially affecting vase life and quality." Vase life increased 5.6% to 17.1% (0.7 to 2.1 days) for roses, 3.2% to 16.7% (0.5 to 2.7 days) for alstroemerias, 12.8% to 34.6% (1.1 to 6.2 days) for gerberas, and 4.6% to 8.8% (1.1 to 2.3 days) for carnations when using the rapid transport systems compared with the 7-day transport system.

The authors added that flowers should not be stored prior to transport and should be pretreated to protect against disease and ethylene exposure when using transport systems. They also recommended that flowers be properly handled and hydrated using commercial floral solutions before and after transport so vase life and quality will be maximized.

The complete study and abstract are available on the ASHS HortTechnology electronic journal web site: http://horttech.ashspublications.org/content/21/4/435.abstract