To change white carnation-type petals to green, stand the long-stemmed flowers in water containing a green aniline dye. Other suitable aniline dyes may be used to achieve colored stripes on white flowers.

Place flowers over a basin of water which contains a very small amount of ammonia in a bell glass. The petals will usually change. For example, many violet-colored petals will change to green; red colors will become green, white will turn yellow and dark carmine will turn black.

Violet-colored asters can be moistened with a very mild solution of nitric acid. The ray florets will turn red and will also acquire a pleasant scent.