What Are Freeze-dried Flowers?

Over the years, more and more different methods of drying flowers have been created and invented.  Years ago, the only methods known were drying by hanging flowers upside down or pressing them under heavy weights.  Later, silica gel was discovered as a wonderful absorbant.  Have you noticed that, when you buy a new pair of shoe, there is a package of silica gel inside?  This is just a demonstration of how we use this knowledge every day.  Microwave drying methods were also discovered and, more recently freeze-drying.  A professional florist might have a freeze-dryer in store because of an increased demand for dried flowers.  Instead of, or in addition to tossing the bride’s bouquet, for example, brides are choosing to freeze-dry their bouquets.  These dried wedding flowers make the perfect reminder of that wonderful day.

Back on to explaining what exactly freeze-drying is.  Unlike other methods, this means of drying is quite costly.  This is why freeze-drying machines aren’t found in every other home!  Because of the high price of the freeze-dryer, many people choose to have their flowers dried by a company with such an apparatus.

Freeze Dried Rose Petals

Once you place your plant and / or flower material inside the freeze-dryer, the apparatus will cause the temperature to drop to below freezing.  The water inside the plant material and flowers will freeze solid.  Once this step is done, the apparatus will then, through a process known as sublimation, the liquid evaporates out of the plant material.  The reason why this process is so specific and interesting is because the frozen liquid evaporates and directly changes from a solid to a gas form without becoming a liquid.  This is significant because other drying methods cause the liquids to evaporate from liquid to gas form.  Freeze drying is truly a completely different drying method.

The process takes longer than most other drying methods.  It usually takes about 4 weeks for the plant material and flowers to be completely dried.  Also, when hanging your flowers in order to dry them out, many flowers can be kept as a bunch and dried while still tied together.  However, when it comes to freeze-drying, each flower needs to be separated in order to maintain the flowers’ integrity.

Unlike other drying methods, freeze-drying will not be affected by exterior factors such as sunlight and wind.  The flowers are safe inside the machine and will only be removed once the process is complete.  Of course, once they are dried, they will need to be cared for in the exact same way as you would any other dried flower.  That means: keeping them out of the sun even after they are dried, keep them out of any drafts and, when storing them, place them in a container that can be sealed properly and kept in a cool, dry place.  An additional process that you can use with freeze-dried flowers is to dip them in a special solution that will help prevent them from becoming too brittle.