Happy Valentine's Day, everyone.
The advice is pretty straightforward. The key components are:
Food. "This necessary combination of acidic water and sugar describes 7-Up or Sprite, says William Miller, a professor of horticulture at Cornell University. One can of either is loaded with citric acid that lowers the pH (increases the acidity) of the soda and contains about 38 grams of sugar."
Preservative. "Vodka has a different effect on a bouquet of flowers: When added to a vase, it preserves them, probably by inhibiting ethylene production...", but only in tiny quantities.
Bactericide. "...a few drops of bleach to kill the bacteria."
Trimming. "When the flowers arrive home, half an inch to an inch of the stem should be cut off. This prevents air from being sucked into the stem and creating a blockage in the plant's uptake system, Miller says. Also, removing the ends physically removes any bacteria that might be growing there, he adds. Roughly every three days another inch should be cut from the stem bottoms and the bouquet should be placed in a clean vase."