Cutting Your Flowers
Cut flowers in your garden in the morning before the dew has dried, or in the early evening. With stem-cutting shears or sharp pruners, snip above a node or dormant bud to spur new blooms. Put stems in a pail of lukewarm water as you cut them.
Re-cut the Stems
Re-cut stems on a slant indoors under water to eliminate air bubbles that block uptake of food and water. Certain types of flowers (including celosia, sunflower, and zinnia) benefit from scalding the stem ends in boiling water for 20 seconds or over a candle flame to stop nutrient-rich sap from oozing. To prevent decay, remove bruised leaves and foliage below the water line.
Condition flowers several hours before arranging. Rest stems in lukewarm water in a cool, dark place so they can absorb water.
Arrange conditioned flowers in a vase of warm water. To slow aging, place the vase in a well-ventilated, cool place (as low as 38° F). Don't store flowers near unsealed fruits and vegetables, which produce ethylene, a gas that hastens ripening, or in the case of flowers, aging.
Freshly cut flowers have enough stored sugars to survive in a vase. But if you would like to add a preservative, try a homemade version. Tests have found commercial floral preservatives to be less effective than the following formula; the sugar in the 7-Up provides energy for the flowers, and the bleach controls bacteria. If you need more liquid, just increase the amounts proportionately.1 cup regular 7-Up®
1 cup water
1/2 teaspoon household bleach
Change water every couple of days. In mixed bouquets, some of the flowers may give off sap that is toxic to other varieties in the vase shortening their vase life, a process that is avoided by frequently refreshing the water.
Tips for Your Cut Flowers
Some of the best and most widely adapted annual cut flowers with the longest vase life include: alstroemeria, aster, celosia, cosmos, gypsophila, lavatera, rudbeckia, scabiosa, snapdragon, statice, sunflower, yarrow, and zinnia.
Keep in mind that flowers with hollow stems do not have a long vase life.
Photography by Suzanne DeJohn/National Gardening Association. Article courtesy of the National Gardening Association