What kind of Hydrangeas are you trying to dry? Some dry better than others.

I would recommend the following web site www.kochcolor.com this company has a lot of experience in coloring flowers and other floral items.

I have read that much of our failure in drying hydrangeas is because we pick them too soon and we should wait until they feel papery. My plant is blooming now so will be experimenting.

I agree that the secret is to wait until the flowers feel corky. Then you cut them with long stems, remove all of the leaves, and put them in a 2 liter soda bottle with a couple inches of water. They will take up the water, if they need it, and will dry perfectly. Truthfully, if you wait until the right time, you don't even need to do that!

I have several blue, dried hydrangeas that were picked when they still had some color, but didn't require any water at all. They went right into an arrangment.

?? I let them dry on the plant, and don't pick anything until late september.

you can add food coloring to the water when you cut them fresh, and they will draw up at least some color- but I've had better luck using one of those crft spray colors.

I grow the oakleaf kind, with the long flower clusters, and I think they turn wonderful colors on thier own when they dry.