Zinnias

Vase life: 5 to 10 days. Talk about a sure thing. No matter what color (all but blue), blossom shape (button, single, double, dahlia, cactus), bloom size (1 to 8 inches) or height (10 inches to 3 feet) you choose -- zinnias grow easily from seed sown where you want plants to grow. Plants withstand heat and drought, and flourish summer to frost in zones 2 through 11. In my survey, only sunflowers got more votes than this reliable annual cut flower. Harvest long stems with tight flower heads; scald stem ends.

Extending Vase Life

If you want your cut flowers to last, try these tips from Lowell Ewart, professor of horticulture and All-America Selections flower trial judge at Michigan State University, and Anne Halpin and Betty Mackey, authors of Cutting Gardens (Simon & Schuster, 1993).

1. Cut flowers before morning dew has dried or in early evening. Snip above a node or dormant bud to spur new blooms. Put stems in a pail of lukewarm water as you cut them.
2. Recut stems on a slant indoors under water to eliminate air bubbles that block food and water uptake.
3. Remove bruised leaves and foliage below the water line to prevent decay.
4. Where advised, scald stem ends in boiling water for 20 seconds or over a candle flame to stop nutrient-rich sap from oozing.
5. Condition flowers several hours before arranging. Rest stems in lukewarm water in a dark, cool place, so they can absorb water.
6. Arrange conditioned flowers in a vase of warm (110°F) water.
7. Put the vase in a well-ventilated cool place (as low as 38°F) to slow aging. Don't store flowers near unsealed fruits and vegetables, which produce ethylene, a gas that hastens ripening.
8. Change water every couple of days. In mixed bouquets, flowers may give off sap toxic to other varieties in the vase.
9. Freshly cut flowers have enough stored sugars to survive in a vase. MSU tests found commercial floral preservatives less effective than this formula. (Increase proportionately if you need more liquid.):

• 1 cup regular 7-Up (the sugar provides energy)
• 1 cup water
• 1/2 teaspoon household bleach (controls bacteria)

Joan Huyser-Honig has contributed many articles to National Gardening.

Photography by Suzanne DeJohn/National Gardening Association and Sabin Gratz/National Gardening Association