If you use colored vases, a good squeeze of lemon, orange, or lime juice will work just
fine. However, they can stain glass, so they are no good if your vases are clear.
For clear vases, use lemonade or Sprite instead. This is a good way to use up the last
drops of your soda as the flowers won’t care if the soda is flat. Don’t use the diet variety
though.
Another useful homemade flower food is to mix two tablespoons of sugar with 2
tablespoons of white vinegar in two pints of lukewarm water.