PRESS DRYING
The flowers and foliages are placed between the pages of a book or magazine or between the
folds of newspaper or blotting sheets by giving some space between the flowers/foliage. These sheets
are kept one above the other and corrugated cardboard sheets of the same size are placed between the
folded sheets so as to allow the water vapour to escape. The whole bundle is then kept in the room. For
quicker drying a herbarium press is kept in a hot air oven at 45°C for 12 to 24 hours depending upon
the moisture in the flowers or foliage. This method is laborious and the time taken for drying is more
than drying in solar dryer/ hot air oven. The press dried material is stored in cardboard boxes. These
boxes are lined with blotting sheets, which keep flowers /foliage dry.
POLYSET
Polyset is a polymer preservation method, which is applied to the flowers / foliage about 45
minutes before drying. It is a chemical pre-treatment application, which is used before air drying to
improve the quality of the dried flowers. Polyset treatment may be applied to the freeze-dried flowers
to hold them together or to help the flowers in retaining their colour for a long duration.