Once you get your fresh flowers into the house, you want to keep them as long as possible. Always place your flowers into water immediately to ensure that air does not plug the stem cells. Once the flowers are in water, try one of these ideas for lengthening the time your flowers stay beautiful.
Commercial preservatives are a mixture of sucrose (sugar), acidifier, a microorganism inhibitor and a respiratory inhibitor, according to the University of Minnesota Extension. Before adding the preservative to the water, clean your container well to get rid of any debris or leftover soap.
Make your own preservative by mixing 1 part lemon-lime soda with 3 parts water. Do not use diet soda. According to the Master Gardeners Santa Clara County, also adding 1/4 tsp. of household bleach per quart will help keep the water clear.
If you don't have soda handy, add 2 tbsp. lemon juice, 1 tbsp. sugar and 1/4 tsp. bleach per quart of water. Freshen the water every four days by adding another 1/4 tsp. of lemon juice.
Never put aspirin or vinegar in your flowers' water. According to the UM Extension, lengthen the life of your flowers by adding water, as needed, every day to your container, keeping the container away from drafts or hot spots, such as radiators or television sets, placing your container in a refrigerator or the coldest spot in the house while you are gone, and keeping apples or bananas away from your flowers. Fruit can emit gases that rapidly age your flowers.