It's wonderful your daughters have taken an interest in flowers. As you've probably discovered, gardening is a great hands-on way to introduce kids to nature.
Kids also gain a strong sense of accomplishment from watching a plant develop and thrive as a direct result of their own effort. The resulting blooms are rewards worth preserving--and conveniently provide great material for crafts.
One of the easiest ways to incorporate flowers into a craft is to press them. Dried flowers are great for a variety of projects, decorating anything from bookmarks and homemade cards to framed designs. Don't worry if you don't have a formal flower press to prepare flowers--this pressing technique works equally well. Just keep in mind that the flowers will take a couple of weeks to dry before use. Once the blossoms are ready, use the paper-thin pressings to create petal necklaces; flowery pendants that preserve a bit of summer's magic.
Another technique to try, called "pounding," uses a rock or hammer to force plant pigments to leave colorful imprints on both cloth and paper. Practice a few simple patterns on paper to get into the swing of it. Then lay out a design on unbleached muslin (don't overlook the leaves of plants--they're often just as attractive as their blooms) and pound out flower prints for a fanciful pillow, tablecloth or a set of botanical bedsheets. Apply this same technique to the plain covers of notebooks to create unique beat-a-leaf journals. These make great garden journals into which your kids can record next year's plant varieties, sowing and germination dates, weather conditions and anything else that takes their fancy.
Finally, nature T-shirts are a fun way to add long-lasting floral prints to your wardrobe. Bleach, in a process similar to stenciling, is used to silhouette the shapes of leaves, ferns, and flowers on fabric. This project isn't limited to T-shirts--you can also capture plant impressions on a cloth bag for a garden tool carryall, decorate the tops of canvas shoes or adorn a pair of pants with whimsical patterns.















