Garden Crafts - Dried Flowers
Source: Gardner's Paradise
Try to choose only the best looking flowers because drying them will
emphasize their imperfections. Pick your flowers late in the morning
when your plants are dry but not yet wilted from to much sun.
Select flowers that are at different stages of development, from
unopened buds to fully open blossoms because flowers will open up more as they dry.
Bright yellow, blue, orange and pink flowers will retain the best color when dried.
If you can't begin drying your flowers immediately, immerse them in a bucket of lukewarm water in a cool, dry place.