The concept of dehydration of flowers is an old on. The idea of using dried flowers developed gradually due to some valid reason. fresh flowers are not available throughout the year. Moreover, vase life of cut-flowers is very limited. This limitation necessitated use of flowers in dehydrated forms. gradually, the process for dehydration of flowers and other plant-pats came into existence and the artefacts prepared using dehydrated flowers became popular.
Initially, some flowers were identified which could be easily dried, preserved and processed in nature. some naturally dehydrated flowers, ferns, leaves, grasses, mosses, berries,see-pods and plant-parts were identified which could be used as decorative items and were available locally.
Flowers were initially dried simply by hanging them. But for preserving the original color and shape, expermentations began in 1949. The technique has now been standardized in such a way that almost all flowers retain their brightness of color and beauty of form after dehydration. Dehydrated floral crafts are commercially important both in the domestic and international market.
Technique of Dehydration
Dehydration means to dry something under artificially produced heat and controlled temperature, humidity and air flow. Dehydration(removal of moisture) of flowers and foliage is done by different methods. The process of dehydration was standardized for different materials as described below.
Air Drying: For this method, only rope/wire and blotting sheets/newspapers are required. Flowers are attached to rope/wire and are kept in hanging positions either in dark or in sun for quick drying. Flower may also be spread over blotting sheets/newspaper and kept in dark or under sun. This is one of the most simple and cheap methods.
Embedding and Drying: To avoid shrinkage and other morphological changes during air drying, the flowers and foliage are embedded very carefully in suitable drying materials(Silical gel) in containers. The embedded materials may be dried in different ways.
Room Drying: The container may be kept in room temperature till the materials are dried properly.
Sun Drying: The container may also be kept in direct sun daily. In this process, dehydration is comparatively faster.
Oven Drying: For quick dehydration, the container consisting of embedded flowers and foliage are kept in the electrically operated hot-air oven at a controlled temperature for specific period.
Vacuum Drying: The embedded materials are dehydrated under vacuum. The vacuum is created under thick walled chmaber fitted with a heating device.
Microwave Drying: The material are dehydrated in microwave oven. Flowers or foliage are embedded in fine silical gel in non-metallic earthen or glass containers and kept in the microwave oven for few minutes.
Maintenance of Shape of the Flower
Flower shape cannot be maintained by air-drying method as the materials undergo shrinkage due to loss of water. Sometimes petals drop down so that the decorative value of flower is reduced. To avoid this situation, flowers are carefully embedded in drying materials. The drying materials support all parts of flowers from all sides so that the originality of material is maintained.
Drying Materials: Borax, Sand, Corn meal and silical gel are the most commonly used drying materials.
Properties of Drying Materials: A wide range of materials has been tested for drying flowers. An ideal drying material should be very fine(0.02 to 0.2 mm) and light in weight, and have no reaction with the flower.
Procedure for Embedding
Embedding is one of the most important processes for dehydration. Silica gel or sand is mostly used as drying material. The containers, mostly used for embedding are small PVC buckets, desk trays, earthen pots etc. The size of container depends upon the size of material to be embedded.
Embedding Individual Flower: When a flower without stem is to be embedded, shallow container (desk tray) are most suitable for this purpose. At first about 2.5 cm thick layer of sand is spread at the bottom of the container. Flowers are arranged on the sand surface. Sand is poured slowly, carefully and gently so that ll gaps in between petals and other floral parts are properly filled up and the original shape of the flower is not disturbed.
Embedding Individual Flower with Stem: Deep containers are used for this purpose. Sand is poured first about 5 to 7.5 cm thick in the container. The stem containing flower is kept in erect position and the sand is poured very carefully from all sides without disturbing the original position of the flower on the stem.
Container used for this purpose should have enough depth. The floweing branch is kept upright with the help of hand or other suppor and sand is poured carefully from all sides. The sand should be poured in such a way that the branches do not bend and are gradually embedded along with flowers. Flowering branches can also be embedded horizontally.
Press drying is one of the most common methods for drying flowers and foliage. Press dried materials may be used for the preparation of greeting cards, wall plates, table tops and for designing landscapes for interior decoration. Normally three methods are adopted for press drying.
Simple method: Flowers and leaves are placed between the pages of an old magazine/book/newspaper sheets which is kept under weight. The magazine/book may be placed between two flat wooden boards for maintaining a uniform pressure. newspare sheets are changed every day till the material gets dried.
Herbarium method: The plant materials are kept between newspaper or blotting sheets which are arranged between two felt driers. The driers are staked between corrugated boards. The board is placed between two wooden frames which are tightened with the help of a strap.
Oven method: The drying time can appreciable be reduced if the stakes are kept in oven at an appropriate temperature. Changing of sheets and driers is not required in oven drying.
Factors Influencing Dehydration
Following factors play an important role during the dehydration process:
Temperature: Temperature plays an important role for dehydration. Quality of product and the rate of dehydration are fully temperature dependent.
Humidity: Dehydration process is greatly affected by atmospheric humidity.
Air Flow: Flow of air plays an important role as a carrier of heat from source to materials through embedding/pressing of materials.
For better results and quality product following precautions are advisable:
- Collection of material should be done a day or two after irrigation to reduce moisture content of flowers and foliage.
- Collection of material after the dew and surface moisture is evaporated.
- Flowers and foliage should mostly be collected in dry season and on a sunny day.
- Residual moisture on the material should be soaked with blotting paper.
- Fresh matterials should always be collected for dehydration.
- Material should be embedded immediately after plucking. Long gap of time may cause wilting, resulting in loss of shape and formation of wrinkles.
- One type of flower should be embedded at one time.
- Undesired portions should be removed before embedding.
- Flowers for press drying should be spread uniformaly on blotting paper for ensuring uniform pressure.
- Soft brush should be used to clean any foreign/unwanted material sticking to the dry flowers.
Care after Dehydration
Dehydrated flowers and foliage are very delicate and need special care during handling for their further processing.
- Embedded flowers and foliage after dehydration should be taken out very carefully by tilting the container.
- Dry flowers absorb moisture and lose their shape. Therefore, they should be stored immediately in moisture-proof containers.
- Storage containers should have the provision of sufficient cushioning for the storage of dehydrated materials. The most common material used for this purpose is cotton and wax paper.
- A small quantity of silica gel should be placed at the bottom of the container to remove the moisture.
- They should be protected from light and direct sunlight otherwise the color of dry flower fades. The glass containers should be kept in a dark and cool place.
- They should be handled very gently and carefully as it is very brittle and fragile. A slight pressure detaches the petals.
- Storage containers should be dust-free. Dust particles spoil the beauty of flowers both by its appearance and absorbing moisture.
- Pressed flowers should be preserved in blotting sheets under slight pressure.
Flowers suitable for Dehydration
During the process of standadization, it has been found that following flowers can easily be dehydrated and they retained their oriignal color and shape suitable for making artefacts:Acroclinum, Bougainvellea, Candytuft, Chrysanthemum, Dahlia, Gerbera, Helichrysum, Ixoras, Marigold, Narcissus, Pansy, Statice.
List of plants suitable for specific technique of Drying
Air Drying: Acroclinum, Clarkia, Coreopsis, Gamolepis, Helichrysum, Limonium, Lobelia.
Press Drying: Candytuft, Chrysanthemum, Euphorbia leucocephala, Galphimia nitida, Lantana, Ixora, Larkspur, Pansy, Pentas carnea, Roses, Verbena, the foliage of Cassia biflora, ferns and Grasses.
Oven Drying: Acroclinum, Bougainvillea, Candytuft, Chrysanthemum, Dahlia, Delphinium ajacis, Euphorbia leucocephala, Gerbera, Gomphrena globosa, Helichrysum bracteatum, Narcissus, Nymphaeaspp., Rose, Tagetes erecta, Tagetes Petula and Zinnia linearis.
Microwave Drying: Antirrhinum majus, Bougainvillea, Callistephus chinensis, Chrysanthemum, Dahlia(Pompon variety), Delphinium ajacis, Dianthus caryophyllus, Gerbera, Helichrysum bracteatum, Helipterum Roseum, Ixora coccinea, Lagerstroemia indica, Narcissus spp., Nymphaea spp. and Phlox.
Retention of Color
It has been observed that the yellow flowers retain their color but white flowers become off white after dehydration. Red, blue and other bright color flowers become considerably dark after dehydration.
Preparation of Artefacts
Dehydrated flowers and foliage have multipurpose applications. Press dried flowers and foliage can be used for designing distinctive and artistic greeting cards, wall plates, calendar, landscapes etc. The art of presentation of these decorative items may be called as ‘Floral Craft’.
They have tremendous potentiality to be suitable substitutes for fresh flowers and foliage for interior decoration and for a variety of other artistic and commercial purposes.
Floral Album/Specimen: Dehydrated flowers may be properly and systematically arranged and a floral album may be prepared for identification of platns.
Dehydrated flowers developed through embedding may be used as specimen for demonstration and for teaching students.
Floral craft as Home-scale Industry: Unemployed youth, housewives and rural women can process various raw materials such as flowers, leaves, fruits, pods, seeds and other parts for dehydration. they can supply dehydrated plant materials to the market or can make saleable decorative items.