Increasing Flowering Potted Plant Longevity Progress Report –September 1996
Date August 15, 1996
Title of Project Increasing Flowering Potted Plant Longevity
Institution where work is being conducted University of Florida
Amount of Endowment Grant $12,000
Covering Period 1/96 to 12/96
Anticipated Date of Project Completion/Final Report December 1996
Individual(s) Conducting Project:
(List Project Leader First)
Terril A. Nell - Title Professor and Chair
Telephone Number (904) 392-1829
Jim Barrett - Title Professor
Increasing Flowering Potted Plant Longevity
- Terril A. Nell and James E. Barrett
- University of Florida and North Carolina State University
- August 1996
- OBJECTIVE: To evaluate the production, transport and retail conditions
which increases the longevity of flowering potted plants.
- SUMMARY OF WORK COMPLETED:
- A. Cyclamen
- 1. Fertilizer termination, where fertilizer (150 ppm N) was either continued
until flowering or terminated 2 weeks prior to flowering, was evaluated
on cultivars ‘Julia’, ‘Finlandia’, ‘Sierra n Rose’ and ‘Sierra Scarlet’.
At marketability, plants were sleeved, boxed and held at 5C for 3 days.
Plants were then placed at 21C at 70 ftc. to determine the effects on longevity
and quality.
- 2. Transport conditions were tested on ‘Julia’ and ‘Finlandia’. Plants
were produced to marketable state then placed into sleeves, boxed and held
at 5 or 16C for 0, 3, 6 or 9 days to evaluate transport tolerances.
- 3. Postproduction conditions were tested on ‘Julia’ and ‘Finlandia’. Plants
were produced to marketable sta-e then sleeved, boxed and held at 5C for
3 days. At unboxing, plants were placed at 18, 21 or 24C at 50 or 100 ftc.
to evaluate quality and longevity.
- 1. Fertilizer rate and termination studies have been conducted to determine
if there is a relationship to leaf yellowing.
- 2. Flowering plants were sleeved, boxed and held at 4 to 27C for up to
6 days to determine if transport conditions relate to leaf yellowing.
- 1. There was an average increase in longevity of 14 to 20 days when fertilizer
was terminated and there were no differences in the number of flowers that
developed on all cultivars. Plant size and leaf quality was also not affected
by terminating fertilizer. All cultivars lasted a very long time in postproduction
conditions, ranging from an average of 42 days for ‘Sierra Rose’ to 69
days for ‘Finlandia’.
- 2. There were no differences in longevity, quality or the number of flowers
that developed among the transport treatments. The average longevity for
‘Finlandia’ was 45 days and 43 days for ‘Julia’.
- 3. Plants lasted 28 days longer and more flowers developed when maintained
at a postproduction temperature of 18C compared to 24C. An increase in
longevity and the number of flowers that developed also occurred at the
higher light level. Cultivars had similar longevity and responded similarly
to the different postproduction conditions.
- 1. Currently, results are quite mixed. Leaf yellowing appears more related
to time of year (greater in warm periods) than fertilizer regime.
- 2. Leaf yellowing is most commonly observed at transport temperatures of
12C to 21C rather than 4C or 27C. Why? We are checking for diseases and
trying to relate symptoms to leaf starch content and plant respiration.
- 3. At present, we have not identified the solution to this problem.
stage of development at marketability, transport conditions and postharvest
conditions on longevity and performance of other crops such as Gerbera
Daisy, Kalanchoe, Gloxinia, and Begonia are planned to be evaluated.
higher quality, longer-lasting flowering potted plants to consumers.
