How long do dyes keep?
Dyes are usually good for several dozen eggs. They can keep over a few seasons if you only use them sparingly. Of course, they often evaporate somewhat, but you can add a little distilled water to bring them back up. They might also lose their intensity over time; to counteract this, you can add a little vinegar. Be sure not to add it to the colors that don’t ordinarily take vinegar, like orange and pink.
