A bouquet of flowers can be preserved by hanging or through the use of agents such as borax, glycerine or silica gel. The best approach depends on the type of flowers to be preserved.
Hanging flowers to dry is the easiest approach. If the bouquet is large, it should be separated into smaller bunches and hung in a way that the flowers are not touching one another. This method works best in a warm, dark, dry room with good air circulation. Hanging flowers to preserve them may cause their colors to fade.
A bouquet can also be preserved by replacing the water in the flowers with glycerine. Flowers are placed in a vase with a mixture of glycerine and water. After two to three weeks the bouquet is taken out of the mixture and hung to dry to spread the glycerine to any petals that may have wilted.
Placing flowers in a box with silica gel also preserves them through drying. Flowers are placed on a layer of silica gel and covered with additional gel. After three to five days they are preserved. Silica gel can also be used to dry flowers in a microwave, according to ProFlowers.
Borax mixed with oatmeal or cornmeal can also be used to preserve a bouquet. The borax mixture is sprinkled over flowers that have been placed standing up through holes punched in a cardboard box. The bouquet is preserved after two to three weeks of drying.