The vase life of cut flowers varies widely by species and is, in part dictated by nature but is also dictated by the care, conditioning and storage conditions the flowers are exposed to. Ample fresh water, controlling bacteria in the water, keeping the stems clear for water uptake and keeping the flowers away from extremes of heat and cold all contribute to keeping cut flowers fresh and at their peak beauty for as long as possible.
Prepare a scrupulously clean vase or watertight container to store or display your cut flower stems. Wash and scrub the interior with soap and hot water to remove any bacteria. For vases with caked on brown or white residue soak with hot water and a teaspoon of bleach for several hours before washing and rinsing thoroughly.
Remove the excess foliage from each flower stem stripping off any leaves or branches that will fall below the water line in the vase. This will keep the vase appearance tidy and help to prevent the build-up of bacteria.
Fill the clean vase 1/2 to 2/3 of the way full with cool to tepid water. Add in a single packet of commercial floral preservative swishing the water to dissolve and distribute the preservative. As a homemade preservative alternative add 2 to 3 drops of household bleach and 1 teaspoon of granulate white sugar to the water and swish to dissolve and combine.
Hold each stem under a faucet running with tepid water and make a fresh cut on the stem at the desired length. Place the cut on the bias to increase the surface area that the stem has to drink up the water. Immediately place the freshly cut stem into the prepared vase water. Repeat for each flower stem.
Place the vase or container filled with flowers in a cool location away from direct sunlight and away from radiators, heating or cooling vents.
Replace the preservative treated water daily or every other day. With each water change make a fresh cut on the bottom each stem removing 1/4 inch with each bias cut.