Freeze dry process provides the best floral preservation currently available, which maintains the natural shape, color and texture of the flowers. The drying process is done using advanced equipment, which consists of a product chamber, vacuum pump and condenser. The flowers are placed in the equipment and frozen. Once the flowers are completely frozen (at -29 C), the water is removed from the flowers in the form of water vapour (this process is called sublimation) through the application of vacuum and small amount of heat (by increasing the temperature gradually from -29 C to room temperature over two to three weeks period). This sublimation process continues for many days while the flowers gradually dry out. The process is slow (takes two to three weeks) and can not be accelerated, because overheating the material can significantly change the composition and structure.
The preservation process involves the following steps:
1. Photographing of the bouquet.
2. Taking apart the bouquet.
3. Re-hydrating each flower.
4. Pre-treating each flower individually to retain their natural color, be more durable and shatter resistant once dried.
5. Freeze drying of the pre-treated flowers in the freeze dryer.
6. Post-treating each flower individually to add durability, elasticity, water resistance, and UV resistance.
7. Redesigning of the flowers in the frame using the photo to resemble the original bouquet or other design as the clients' desire.
The whole process may take 4 to 8 weeks to complete. The freeze drying process is very labour intensive and time consuming. However, this state of the art technique gives the most natural looking preserved flowers. Almost any type flowers can be freeze dried. Flowers such as bouvardias, chrysanthemum, and lilac do not freeze dry well. The quality of the freeze dried flowers depends on the quality of the fresh flowers prior to freeze drying. The colors of the flowers may change slightly after the freeze drying process. Depending on the types of flowers, the color may lighten slightly or become richer and deeper. With time, the hues may soften and acquire more of an antique look.
With proper care, your freeze dried floral keepsakes will last for many, many years to come. They should be displayed in encased frames or containers and kept away from direct sunlight, humidity and rough handling.