Question: I have a lot of hydrangeas and the flowers are so pretty. How do I dry the blossoms?
Answer: To dry them naturally, allow the flowers to dry on the plant until the end of summer. Cut the blossoms, with as much stem as you desire, when the nights are cool but before the first frost. Remove the leaves and place the cuttings in vases without water. You can hang bunches of flowers upside down, but it's not necessary.
For nearly perfect blooms, consider drying them in silica gel. This process is more expensive and time-consuming. The instructions are available on the container of silica gel, available at craft stores.
Working with the dried blossoms can cause a lot of breakage. If you're making a wreath, soak the blossoms in water to soften them. When they're pliable, begin your project. After it's done, allow it to dry again. This will take about a day.
-Beverly Shaw, Advanced Master Gardener, Purdue University