Dried flower processors use various techniques to dry their products:
HANGING IN A VENTILATED AREA
This technique generally takes about three to four weeks for the flowers to dry, depending on the facility’s humidity. A disadvantage to this technique is that, during the drying period, florals are subject to botrytis and insect infestation. The colors of flowers dried via this technique also can fade or turn brown. As a result, this technique is not typically used by modern commercial dried flower producers.
HOT-AIR DRYING ON RACKS
This technique forces very hot air through a tunnel in which the flowers hang. The hot air pushes the moist air out the other end. This technique has disadvantages because it typically causes dry, brittle florals with no green plant parts and no aroma. This is sometimes referred to as “Kiln Drying”.
CHEMICAL DRYING
This technique involves covering the flowers in a desiccant such as silica gel, calcium chloride, borax or sand. The moisture in the flowers is transferred to the desiccant where it is retained. This technique can take a little longer than other methods, but it provides more colorful, higher quality dried flowers and foliage than the previously mentioned methods.
CHEMIDESICCATOR(c)
Drying machines developed and used exclusively by Mirsky, Inc., dries the flowers rapidly (3 – 5 days) at temperatures below 90 degrees F. This process produces superior results. In this process the flowers are hung on racks and placed in the driers. The flowers are then encouraged to give up their water naturally and without denaturation. The flower’s color is more vibrant and their aromas retained. They are less brittle and the natural green color of their stems and leaves are retained.
PRESERVED FLOWERS AND FOLIAGE:
Here the flowers and foliage are freshly cut and placed in a preserving solution, usually containing humectants such as glycerin or other glycol. The solution is usually absorbed systemically and replaces the natural moisture of the plant’s tissues. This allows plants to retain flexibility and a realistic appearance; however, the natural color is destroyed in the process and needs to be supplemented with dyes.
MECHANICAL DRYING
Freeze-drying machines do an excellent job of removing moisture from florals. Because the equipment is expensive, however, flowers dried using this method typically cost more than flowers dried using other techniques. Modern coating techniques have largely reduced the brittleness of the delicate flowers that have been dried by freeze-drying. Unfortunately the natural green color of stems and leaves is lost in the process.
PRESSING
Pressed flowers are produced by mechanically flattening blooms between absorbent layers of materials that draw the moisture out of the flowers.