Contact: Diane Relf, Extension Specialist, Environmental Horticulture
Posted April 1997
You can prolong the life of cut flowers by giving them special attention when they are picked. A little extra care at that time will cause them to last longer in arrangements, or be more attractive throughout a flower show.
Cut flowers early in the morning or late in the evening when they are holding their maximum amount of water. If picked during midday when stressed and wilting from lack of water, the flowers may not fully recover and need to be discarded. They should be cut several hours before they are to be used to allow time for conditioning.
Regardless of what you may have read or heard, there seems to be no real preference for morning or evening as the best time for cutting. Flowers and foliage may be somewhat more turgid in the morning, especially if the soil in the garden is somewhat dry. They will have a slightly higher supply of reserve foods in late evening, but may be less crisp because of water loss during sunny hot weather.
Most flowers should be cut before they open fully. They will retain their attractive form longer than if cut when mature. Flowers which open rapidly like roses and poppies should be cut when the buds show color.
Use a sharp knife or pruning shears when cutting flowers. Do not use household shears which will mash the stem and slow the absorbtion of water by the flower. Make a clean slanting cut. A square cut may allow the stem to rest flat on the bottom of the container and reduce water uptake.
Strip off any lower leaves which will not be needed in the flower arrangement. Immerse the stems in warm water at about 110 degrees. Flowers with shiny or leathery foliage, such as the peony and rose, may be immersed up to the flower. Do not immerse leaves which have a soft or fuzzy surface. Flowers with soft pulpy stems like tulips should be immersed in only two or three inches of warm water as the stems soften quickly.
Flowers like poppy and poinsettia will bleed a milky sap when cut. This may be prevented by plunging the stem into ice water as soon as it is cut, or putting the base of the stem in boiling water for 30 seconds, or by searing the cut end with a flame. Then place the stems in warm water for hardening as suggested above.
To ensure long life for your flower arrangement or display, harden the flowers by covering the blooms with wax paper or loose plastic bags to reduce transpiration. Store the arrangement in a cool dark place out of drafts for 2 or 3 hours then unwrap and display. Avoid conditions which will increase transpiration or wilting. Do not place flowers in direct sun or drafts, or near hot radiators or electric lights.
The use of flower preservatives in the water will extend the life of cut flowers. These materials contain sugars to provide nutrients, acids to prevent bacterial growth, and a fungicide to reduce the possibility of disease. The addition of aspirin or alum to the water will not help, and the use of salt may be harmful.
Mashing woody stems will not increase water intake but may make it easier to insert such stems on a pinpoint. Square cut stems of herbaceous materials may be easier to hold on a pinpoint than those with a long slanting cut.
(Prepared by J.T. Foley, Extension Technician, Consumer Horticulture, Virginia Tech, from Virginia Cooperative Extension materials.