There are many measurable factors which both positively and negatively affect the post-harvest life of flowers, including the type species or 'cultivar' of the flower (such as Osiana roses, for example) the growing media, light, temperature, humidity, the maturity of the flower at the time of harvest, the time the flower spends in cold storage prior to consumer purchase, the amount of ethylene gas around the flower, and the cleanliness of the water in which the flower is stored and displayed. Everyone who handles the cut flower, from the grower to you, the consumer, affects the longevity of that flower. We offer the following information so that you can learn how a flower reaches you and how you can help fortify its lifespan.
Cut flowers travel through many hands before they reach the consumer. The goal of each handler is to prolong the flower's life. The grower who grows the flower has perhaps the greatest control over the quality and longevity of the flower because he controls most of the factors influencing flower life, namely the type of cultivar, the growing media (including fertilization), the flower's maturity, and the light, temperature and humidity conditions during growing. When the grower harvests the flower it often spends 24 to 48 hours in the process of being graded, packaged and shipped. Since, most flowers are grown outside the US, the grower ships to an importer who then stores the flower for a brief period, usually a day or two, before shipping the flower to a wholesaler.
A wholesaler may hold the flower for as long as three days before a retailer purchases the flower. A retailer may also hold the flower for up to three days before the consumer makes a purchase. Hence, a harvested flower may spend anywhere from 8 to 10 days before it reaches the consumer. While being transported between these various handlers, the flowers are kept at a very low temperature thereby significantly slowing the flowers' physiological development and, in turn, prolonging their life.
Temperature, water quality and ethylene gas are the most significant factors affecting the longevity of the post-harvested flower. Most flowers are shipped dry to the wholesaler, who then puts the flowers in water for re-hydration. The flowers travel in refrigerated trucks or are pre-cooled and packed with ice for transportation by air. The grower, importer, wholesaler, and retailer do their best to maintain the temperature of the transported flower at approximately 34 degrees Fahrenheit.
Temperature greatly affects the post-harvest performance of flowers. While cut flowers can last up to three weeks when maintained at temperatures of 34 degrees, they normally last 5 to 6 days at room temperature. Though the shipping process is carefully monitored, sometimes warming and its resulting stress on the flowers occur at some point in this process of moving flowers from the grower to the consumer, and so the flowers' lifespan is shortened. It can occur, for example, when a South American grower sends his pre-cooled, ice-packed flowers to the airport for shipment to Miami, and the airline holds the boxes on the tarmac under the hot sun because the plane is late. The flowers may warm to 60 or 70 degrees for a time.
The grower, importer, wholesaler and retailer are unaware of the warming that occurred on the tarmac. As usual, they carefully care for the flowers, which will not likely show any signs of stress until the retailer learns of their shortened lifespan in your home. This is just one example of an unfortunate and unforeseen case of temperature stress.
Stress from temperature changes can also occur in your home. Flowers may be placed too near drafty doorways or furnace vents, or when adding or changing water in the vase, people may use water that is too hot or cold. Any fresh water added to the floral container should be at a moderate room temperature. By considering the air and water temperatures you can decrease temperature stress on your flowers and help prolong their life.
If you wish to learn more about the effects of temperature on the post-harvest performance of flowers, including its effects on transpiration and respiration, then please click here to learn more about the effects of temperature on Post-harvest Performance. Please keep in mind that the additional information obtained from this link and all subsequent links on this page are directed toward wholesalers and retailers.More >>