Cutting your own fresh flowers from your garden ensures you are always just a few steps away from getting them into a vase and under the right conditions for a long life. Distractions can sometimes interfere and the flowers may still end up out of water for a period of time. Although most flowers can survive for a short period without life-giving water, it can shorten their overall bloom once you do get them into a vase.
To Wilt or Not
Flowers have a different lifespan after cutting, depending on the variety and the health of the plant you cut from. Most flowers begin to decline as soon as they are cut, although visible signs of water stress may take several hours before they become obvious. Delicate flowers that wilt easily in the heat of the day when they are still on the plant, like poppies (Papaver spp.), which grow in U.S. Department of Agriculture plant hardiness zones 2 through 7, may only last an hour after cutting if they aren't immediately provided with water. Hardier flowers, like roses (Rosa spp.), which grow in USDA zones 4 through 11, can survive a couple of hours without water if they aren't stressed by other environmental factors. If the petals appear limp or begin to wilt, it's a sign the flower needs water immediately if the bloom is to survive.
Some Like It Hot
Heat and direct sunlight cause cut flowers to wilt more quickly after cutting, especially if you can't get them into water right away. Improve longevity and give yourself more time to get from the garden to the nearest vase by cutting flowers early in the day when it's still cool, and by keeping the flowers in a shady spot until you bring them indoors. Wrapping the stems with plastic cellophane or with a moist paper towel helps prevent them from drying out in the short time they are left without water.
The First Cut
Proper cutting further helps ensure a longer life. Avoid flowers that are fully open or that have brown or damaged petals. Disinfecting your shears by wiping them with isopropyl alcohol further helps minimize fungal and bacterial growth that can shorten flower life. Although the flowers can survive for a short time without water, bringing a bucket of warm water with you and immediately placing the cut stems in it increases the chances of survival and a long life. Even a few minutes without water can cause the stems to dry out or the petals to wilt, making it difficult for the flower to take up water later in the vase. Air bubbles can also become trapped within the stem, which also prevents later water uptake.
A Long Life
Removing the lower portion of the stem can help increase water uptake and vase life if the flowers weren't placed in water immediately after cutting. Remove about 1 inch from the bottom of the stem, cutting at an angle and keeping the stem under water as you cut so air bubbles aren't trapped within the stem. Allow the flowers to harden off by placing the bucket in a cool area or in the refrigerator, away from ripening fruits and vegetables, for two hours. When you are ready to arrange your flowers, dissolve a floral preservative in the vase of water and transfer the stems over to the new container, without giving them a chance to dry out. Make sure no leaves are under water or they may rot and shorten the flower's life. Flower life in the vase varies greatly, with short-lived poppies surviving about seven days and longer-lived roses lasting up to two weeks. Change the water every two days and remove old flowers as they wilt to further extend the life of your bouquet.