How do you keep your flowers fresh? We have all heard the folklore as well as my Grandma’s resolute instructions: a little bleach, a touch of vinegar, a splash of vodka. Add some sugar or 7-UP, aspirin, vitamin C, Listerine, and pennies, too. What works, what doesn’t, will it make a difference and will it harm my flowers?

Many home remedies have a thread of truth as their basis. Bleach, vinegar, vodka, hydrogen peroxide and Listerine are antibacterial agents. They work to keep the water clear and clean to allow the flowers to drink and rehydrate fully without clogging from bacteria. Sugar, 7-UP and Listerine have sugars that “feed” the flower as it drinks the water mixture. Lemon juice, vitamin C and aspirin are wetting agents (acidifiers). They lower the ph of the water so the flower will drink more rapidly.

What about the use of pennies? Now that is an interesting remedy. Copper is an antibacterial agent, and when pennies were made of real copper, they would release enough copper into the vase water to have an effect. But modern pennies, which are not made of copper, will have no effect other than making your vase of flowers a few cents more valuable.

While home remedies can work, they also can harm your flowers if applied improperly.

Thank goodness for professional flower food. No conjecture and no concerns. With proper treatment, many flowers can easily last a week or more. Even my Grandma would be impressed.

Flower foods include an antibacterial, a sugar and a wetting agent. All three together in the proper proportion and ready to mix with water. Follow the recipe on the container, and you can extend the life of your flowers by days. Some varieties react so favorably to proper flower food that they will live twice as long as they would with pure water.

With the use of professional flower food, roses will bloom more fully. Gerberas will stand tall without the dreaded “bent neck.” Carnations will last for weeks, and peonies will bloom full and lush.

One of my friends who is a flower care expert says it best: “Embrace the handling techniques grounded in scientific research and proven facts. The goal achieved — flowers that last.”

For more flower care advice, visit aboutflowers.com.