Pressing flowers is one way of drying flowers to preserve them. Artists and crafters use pressed flowers for decorative projects, and scientists use them to study botanical specimens. Although it is possible to buy flowers already pressed, many people enjoy gathering and pressing their own flowers. There are flower presses available or you can make your own. It is even possible to press flowers using readily available heavy objects, such as books.
Gather flowers in the afternoon, when their moisture content is low. Select plant materials that are fresh and have not started to fade. Press flowers as soon after they have opened as you can. If you cannot press them within a few hours, store the plants in a clean vase that contains water with flower food added.
Arrange flowers on a piece of smooth, absorbent paper, such as construction paper, blotter paper or newspaper covered with a piece of tissue paper. There should be some space between the flowers so petals do not overlap. All of the flowers on any one piece of paper should be of similar thickness. Put a second piece of the paper on top of the arranged flowers.
Place the sandwiched flowers in a flower press and tighten the screws. If you are using books, place the flowers between the pages in the middle of one book and weight with two to three additional books. Store the press or books in a warm, dry area.
Check the flowers carefully after about three days and replace any damp paper. Continue pressing as long as moisture remains in the flowers. It can take up to a week for pressed flowers to dry completely.
Remove the thoroughly dry flowers from the press or book. Use a thin knife to lift the flowers from the paper. Store the flowers, layered between sheets of absorbent paper, in a cardboard box or plastic container until you are ready to use them.
Use a botanical flower press. These are designed for maximum air flow during pressing, which can speed up the process and protect against rotting. Shorten drying time by starting the process in the microwave. Use a microwave press and process in several half-minute to one-minute intervals, allowing the flowers to cool thoroughly between intervals. Flowers with a single layer of petals are best for pressing. Thicker flowers, such as lilies and full-size roses, require additional preparation for successful pressing.
Be sure a pressed flower is completely dry before using. Incompletely dried flowers can mildew, which ruins the specimen itself and, possibly, the project in which it was used.