Soak loose flowers in room temperature water and in a dimly lit location for several hours or overnight. This lets the plant tissue fill with water.
Remove any leaves or thorns that will be underwater when you fill the vase.
Prepare a floral preservative according to the package instructions using water between 100 and 110 degrees Fahrenheit. Fill the vase with the prepared water. Refill the vase as necessary, and change the water when it becomes cloudy.
Avoid overcrowding a vase. Too many flowers puts pressure on the stems and prevents them from absorbing water.
Keep flower arrangements away from direct sunlight and drafts.
Remove wilted flowers. If there are several flowers on the stem, clip out the wilted ones with hand pruners or scissors.
Trim the bottom of the stems when they go limp or when the flowers droop. Limp stems usually means they aren’t taking up water. Hold the stems under water, and cut 1 or 2 inches from the bottom using hand pruners.
Keep flower arrangements away from fresh fruit. The fruit emits a gas that shortens the life of your flower arrangement.