Horticulture Principles and Practices

POST-HARVEST PHYSIOLOGY (SCIENTIFIC)
Good and consistent care and handling procedures when using cut flowers/foliage
will pay big dividends in terms of longer vase life. A quality, long lasting flower or
foliage is certainly a major objective of professional florists. Whether flowers are
purchased locally or transported great distances, the basic rules of flower care must
be observed. Cut flowers and foliage, even when separated from the parent plant, are
living, actively metabolizing plant parts. These parts undergo the same aging
processes as the parent plant, however the rate of metabolizing can be manipulated.
This is done by supplying the cut material with its basic needs and by supplementing
those needs through environmental controls and the addition of post-harvest
chemicals. The following table summarizes the major factors that affect the keeping
quality of cut flowers and foliage.
Factor How controlled Who controls
1. Production Plant genetics, growing environment and
management practices
2. Transpiration Lower environmental temperature and higher
environmental
humidity reduce transpiration rate
3. Floral Food Provides energy for plant metabolism, increases
water uptake, helps control bacteria growth in water
4. Temperature Lower environmental temperatures slow
transpiration as well as respiration
5. Humidity Higher humidity reduces transpiration and the need
for the flower to absorb large quantities of water
6. Ethylene Ethylene scrubbers on the refrigeration system,
chemical treatments such as Ethybloc®, do not mix
fresh fruit with cut flowers in refrigerated storage
7. Microbial Activity Use of floral food greatly decreases microbial activity,
use of clean buckets and storage in a clean
refrigerator also reduce microbial activity
Grower
Wholesaler,
retailer, consumer
Grower, wholesaler,
retailer, consumer
Grower, wholesaler,
retailer
Grower, wholesaler,
retailer
Grower, wholesaler,
retailer
Grower, wholesaler,
retailer, consumer
690 Chapter 24 Cut Flowers and Floral Design
Basic Care and Handling Terms
Acidifier–additive to floral foods to reduce the pH of water for better water uptake
Anti-Transpirant–a spray or dip that reduces water loss from the flower/foliage by
reducing the transpiration rate
Bio-inhibitor–additive to floral foods to reduce the microbial activity in bucket or vase
solution
Citric Acid Hydration Solution–a pre-treatment used prior to floral food to stimulate
rapid water uptake
Conditioning–allowing flowers/foliage to absorb a water floral food solution at room
temperature
Dehydration–excessive loss of moisture (wilting)
EthylBloc R –chemical used to prevent ethylene damage (1-MPC)
Ethylene–naturally occurring plant hormone that causes rapid aging of flowers
Floral food–contains three primary ingredients to prolong the vase life of cut
flowers/foliage; 1. sugar (dextrose) for energy, 2. bio-inhibitor to reduce microbial activity,
and 3. acidifier to lower water pH for better water uptake.
Hardening–allowing flowers/foliage to cool in a refrigerated environment