Silica gel absorbs 40 percent of its weight in moisture and dries flowers in approximately a week. These granular crystals are sold in craft and garden supply stores. They are more expensive that other flower drying formulas but are preferred because of their speed in drying vegetation and their unique quality of changing color according to the amount of moisture they absorb. It turns light pink when exposed to moisture and returns to its original blue when dried, restoring its moisture absorbing capacity.
Select a metal or plastic container with an airtight seal for drying flowers with silica gel. A shallow, flat container works well, as the weight of the gel is more evenly distributed, minimizing damage to flower petals.
Pour a layer of silica gel 1 ½ to 2 inches thick on the bottom of the container. Place daisies, cone flowers, cosmos and other flat-faced flowers face down, so the petals rest against the silica beads. Snapdragons, larkspur and others that grow on spikes dry best when laid flat on the silica. All others dry best when placed face up.
Fill in around the petals with additional granules until the flowers are covered. Pouring silica around the edge of the container and tapping gently to move the beads in place reduces the risk of damage to flowers. Cover the flower blossoms by ½ to 1 inch, and replace the cover. Seal tightly.
Check flowers in one week for dryness. Petals should feel dry and papery. If flowers are not adequately dry, reseal and allow to set for another week. The size, shape and moisture content of flowers determine the drying time. (See Resources for typical drying times.)
Gently pour off or scoop away silica gel to expose dried flowers. Flowers exposed to high humidity may reabsorb moisture. Store in an airtight container with silica gel when not in use.