Many garden and arrangement books include the comment about cutting stems under water to help prolong the life of the cut bloom. The faster you can do so the better. Take two containers of water with you whenever you cut flowers in the garden. The smaller container is for cutting the stems in water after they have been cut off the plant. The second is where you place the blooms after you have re-cut the stems. By re-cutting the stems in water, you will keep air from filling the capillaries in the stem. If the capillaries are full of air, water will not be able to move up the stem and keep the bloom fresh.

Some practices are based on folklore rather than science and common sense. My mother told me to put crushed aspirin in the water to make cut flowers last longer. She should have told me to disinfect the vase instead; that would have had a more beneficial effect. Giving algae, fungi, and bacteria a head start by not using clean vases, supports, and cutting tools is a good way to shorten the life of your cut blooms.

Reusing Oasis or Capri also contributes to short bloom life. I've done that too. My mother said it was a shame to be wasteful and it wouldn't do any harm to reuse it even if it was "slightly slimy" and had a slight odor. She still has string, aluminum foil, and other things (don't ask!) that she started collecting over twenty years ago. She thought she might need to reuse them someday.

My mother also said to use one-part 7-Up mixed with three parts water particularly for cut roses. That tip is closer to being useful. Cut roses need feeding even though they've been cut from the bush.