Flowers, when they are cut, are still living organisms that have had their main food source removed. To keep them alive, flowers require placement in water and a steady supply of sugars to reduce flower wilting. Commercial preservatives provide these sugars, as well as do acidifiers that change the water pH to better accommodate the flower, microorganism inhibitors that prevent disease in the flower, and respiratory inhibitors that slow the flowers' metabolism. Proper care with a good preservative bought from a garden center will extend the life of cut flowers to several weeks in some cases.
Fill a vase with water so the water touches the bottom of the cut flower stems.
Cut the flower stems at a 45 degree angle to aid in water absorption. The angle will also prevent the stem from lying flat on the bottom of the vase, which inhibits water absorption, says Jeff Rugg of the University of Illinois.
Remove the lower leaves of the flowers to keep them out of the water. Dying leaves will spread bacteria throughout the water, causing infection.
Add preservative to the flower water and mix according to the instructions on the packaging.
Add the flowers to the water and set the plant in a cool place, away from direct sunlight. Cool temperature hardens the flowers, according to the University of Minnesota, extending the flowers' life.