Postharvest Treatment of Specialty Cut Flowers

As part of our yearly cut flower trials, we conduct vase life studies on cultivars that show potential as future mainstays on growers’ lists. The past two years, thanks to a joint NCDA and USDA grant, we also had the opportunity to evaluate some cultivars that are already widely grown in North Carolina. A total of 57 annual and perennial cut flowers were evaluated for postharvest vase life during the 2012 and 2013 seasons.

Trial varieties were planted in four plots of sixteen plants each. All marketable flowers were cut, measured, and recorded in the field three days per week. Up to 60 stems per variety were sorted into four uniform groups and bundled for postharvest vase life evaluation.

Bundles were placed into their first solution for four hours. Then they were transferred to a second solution for 48 hours. The first treatment, a hydrator, is intended to promote rapid water uptake and does not include sugar, while the second treatment, a holding solution, has sugar to promote long vase life. The four resulting treatments were:

  1. Hydrator only (no preservative)
  2. Holding preservative only (no hydrator)
  3. Hydrator, then holding preservative
  4. De-ionized water only (control)

Once pretreatments were done, each stem was placed in its own mason jar in conditions simulating consumers’ homes. Stems were checked daily and terminated once they reached an agreed-upon stage of expiration.

The results of these postharvest evaluations give growers information that helps them make decisions about the best cut flower varieties to include on their farm.

– H. Granitz