Flower preservation has existed since early

history History is the systematic study of the past, focusing primarily on the Human history, human past. As an academic discipline, it analyses and interprets evidence to construct narratives about what happened and explain why it happened. Some t ...

, although deliberate flower preservation is a more recent phenomenon. In the

Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...

, the bones of pre-historic man were discovered with delicate wild flowers probably as a tribute to a passing loved one. Evidence of deliberate use of specific flowers is indicated by the pollen grains that were present. Brightly colored and vivid flowers were also found in

Egyptian ''Egyptian'' describes something of, from, or related to Egypt. Egyptian or Egyptians may refer to: Nations and ethnic groups * Egyptians, a national group in North Africa ** Egyptian culture, a complex and stable culture with thousands of year ...

tombs. These flowers were approximated to be 4,000 years old. In the sixteenth century medicinal

nosegay A nosegay, posy, or tussie-mussie is a small flower bouquet. They have existed in some form since at least medieval times, when they were carried or worn around the head or bodice. Doilies are traditionally used to bind the stems in these arr ...

s began to give way to ornamental ones. Flowers essentially started to be used for decorative purposes such as jewels, fans and gloves. During the Elizabethan Age the once familiar ruff was replaced by soft lacy collars, and bosom flowers also became popular. Out of the

Victorian era In the history of the United Kingdom and the British Empire, the Victorian era was the reign of Queen Victoria, from 20 June 1837 until her death on 22 January 1901. Slightly different definitions are sometimes used. The era followed the ...

grew the fascination of communicating with flowers carried in the nosegays. The idea of the

language of flowers Floriography (language of flowers) is a means of cryptological communication through the use or arrangement of flowers. Meaning has been attributed to flowers for thousands of years, and some form of floriography has been practiced in tradition ...

developed, when it was decided that giving and receiving a bouquet of flowers, when the flowers themselves carry a meaning, gives much greater pleasure.

Drying

One of the earliest techniques used to preserve flowers is air drying. Many plant species are capable of retaining their general shape and coloration when left to dry naturally in ambient conditions. Another method involves the use of glycerine, which helps maintain the flexibility and longevity of the preserved plant material. For effective preservation, the plant is fully hydrated before treatment. A solution is prepared using a mixture of lukewarm water and glycerine, typically in a 2:1 ratio. The use of warm water aids in dissolving the glycerine and enhances absorption. However, this technique is not effective when foliage has already begun to display autumnal coloration. Pressing is a widely used method that results in flattened specimens, often used for botanical studies or decorative purposes. This process is also known as Oshibana. The process typically involves placing flowers between sheets of unglazed paper, such as newsprint or pages from a telephone book, ensuring that individual specimens do not overlap. Multiple layers are often stacked and pressed under a flat, heavy object. The drying period varies depending on the species and moisture content but generally ranges from two to four weeks.

Modern preservation methods

Hanging flowers in ventilated area

: There are several air-drying methods used for different kinds of flowers. The easiest and most effective way to dry most flowers is to tie them in small bundles with

twine Twine is a strong Thread (yarn), thread, light String (structure), string or cord composed of string in which two or more thinner strands are twisted, and then twisted together (Plying, plied). The strands are plied in the opposite direction to ...

raffia Raffia palms are members of the genus ''Raphia''. The Malagasy language, Malagasy name is derived from ' "to squeeze #Raffia wine, juice". The genus contains about twenty species of Arecaceae, palms native to tropical regions of Africa, and esp ...

ribbon A ribbon or riband is a thin band of material, typically cloth but also plastic or sometimes metal, used primarily as decorative binding and tying. Cloth ribbons are made of natural materials such as silk, cotton, and jute and of synthetic mate ...

s, and hang them upside down, out of direct sunlight in a warm, well-ventilated place. Bunches should contain one type of flower. Large flowers are dried individually. The leaves stripped as soon as possible after picking. They retain moisture and slow down the drying process. Wall hooks, poles or wires are placed at least from the ceiling. Heads should be staggered to allow plenty of air to circulate. This prevents

mildew Mildew is a form of fungus. It is distinguished from its closely related counterpart, mold, largely by its colour: molds appear in shades of black, blue, red, and green, whereas mildew is white. It appears as a thin, superficial growth consisti ...

and rot. It may be necessary to re-tie bunches or individual flowers half way through the drying process, because the stems tend to shrink as they dry. : The drying period can range from one week to several weeks depending on the type of material, when and where it was harvested and the humidity of the place where it is drying. The stems of hung flowers tend to dry unnaturally straight and the flowers become very brittle. : Suggested flowers to air dry include: strawflowers,

goldenrod Goldenrod is a common name for many species of flowering plants in the sunflower family, Asteraceae, commonly in reference to the genus ''Solidago''. Several genera, such as ''Euthamia'', were formerly included in a broader concept of the genu ...

, ''

Hydrangea ''Hydrangea'' ( or ) is a genus of more than 70 species of Flowering plant, flowering plants native plant, native to Asia and the Americas. Hydrangea is also used as the common name for the genus; some (particularly ''Hydrangea macrophylla, H. m ...

''s, ''

Celosia ''Celosia'' ( ) is a small genus of edible and ornamental plants in the amaranth family, Amaranthaceae. Its species are commonly known as woolflowers, or, if the flower heads are crested by fasciation, cockscombs. The plants are well known in E ...

'' (crested and plumed types), globe amaranth, ''

Salvia ''Salvia'' () is the largest genus of plants in the sage family Lamiaceae, with just under 1,000 species of shrubs, Herbaceous plant, herbaceous Perennial plant, perennials, and Annual plant, annuals. Within the Lamiaceae, ''Salvia'' is part o ...

'', '' Xeranthemum'' and many of the "everlastings."

Hot air drying in drying chamber

: Compact flowers like marigolds,

chrysanthemum Chrysanthemums ( ), sometimes called mums or chrysanths, are flowering plants in the Asteraceae family. They are native to East Asia and northeastern Europe. Most species originate from East Asia, and the center of diversity is in China. Co ...

cornflower ''Centaurea cyanus'', commonly known as cornflower or bachelor's button (among other names), is an annual flowering plant in the family Asteraceae native to Europe. In the past, it often grew as a weed in cornfields (in the broad sense of "co ...

s and

zinnia ''Zinnia'' is a genus of plants of the tribe Heliantheae within the family Asteraceae. They are native to scrub and dry grassland in an area stretching from the Southwestern United States to South America, with a centre of diversity in Mexic ...

s dry well in a fan-assisted,

convection Convection is single or Multiphase flow, multiphase fluid flow that occurs Spontaneous process, spontaneously through the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoy ...

chamber. Non-ventilated chambers are not appropriate, because they generate too much moisture. The material must be dried at a low temperature (30-35˚Celsius), over many hours. The flowers are slotted through holes in a wire mesh rack leaving room for the stems to dangle below. The time required depends upon the density of the flowers.

Silica gel drying

: Another trend is

silica gel Silica gel is an amorphous and porosity, porous form of silicon dioxide (silica), consisting of an irregular three-dimensional framework of alternating silicon and oxygen atoms with nanometer-scale voids and pores. The voids may contain wate ...

. Its initial cost is greater than that of

borax The BORAX Experiments were a series of safety experiments on boiling water nuclear reactors conducted by Argonne National Laboratory in the 1950s and 1960s at the National Reactor Testing Station in eastern Idaho.

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...

or borax-

cornmeal Maize meal is a meal (coarse flour) ground from dried maize. It is a common staple food and is ground to coarse, medium, and fine consistencies, but it is not as fine as wheat flour can be.Herbst, Sharon, ''Food Lover's Companion'', Third Editi ...

combinations, but silica gel can be used over and over for many years. Silica gel dries flowers quickly, so it can be used to dry more flowers during a single season than the same quantity of a borax mixture. Silica gel is available under a number of trade names. It is white, but some types contain blue crystals that act as an indicator of the amount of moisture that has been absorbed. When these crystals are clear blue, the material is dry. As moisture is absorbed from the flowers, the crystals gradually turn pink. At that point, it is time to re-dry the crystals before using them again. : To dry the material, silica gel is spread on open pans or cookie sheets in a layer thick. Materials to be preserved are then baked in an oven at 250˚Celsius for about an hour, or until the moisture-indicating crystals, if present, are blue again. Material is then stirred several times while drying. : Flowers dried in silica gel must be placed in airtight containers. If a container is not sealed tightly, the silica gel absorbs moisture from the air, and flowers dry too slowly or not at all. A candy tin,

plastic container Plastic containers are containers made exclusively or partially of plastic. Plastic containers are ubiquitous either as single-use or reuseable/durable plastic cups, plastic bottles, plastic bags, foam food containers, Tupperware, plastic tu ...

, coffee can, large-mouth jar or any other container with a tight-fitting lid may be used. If no containers with tight lids are available, loose tops should be sealed with tape. Silica gel is especially useful for drying fragile plants and flowers with delicate colors. Flowers that dry best in silica gel are

allium ''Allium'' is a large genus of monocotyledonous flowering plants with around 1000 accepted species, making ''Allium'' the largest genus in the family Amaryllidaceae and among the largest plant genera in the world. Many of the species are edible, ...

, anemone, cornflower,

rose A rose is either a woody perennial plant, perennial flowering plant of the genus ''Rosa'' (), in the family Rosaceae (), or the flower it bears. There are over three hundred Rose species, species and Garden roses, tens of thousands of cultivar ...

tulip Tulips are spring-blooming perennial herbaceous bulbiferous geophytes in the ''Tulipa'' genus. Their flowers are usually large, showy, and brightly coloured, generally red, orange, pink, yellow, or white. They often have a different colour ...

and zinnia.

Molecular sieve

Molecular sieve A molecular sieve is a material with pores of uniform size comparable to that of individual molecules, linking the interior of the solid to its exterior. These materials embody the molecular sieve effect, in which molecules larger than the pore ...

is a material containing tiny pores of a precise and uniform size that is used as an absorbent for gases and liquids. They are metal alumino silicates which have a crystalline structure consisting of an assembly of tetrahedral. The tetrahedral are made up of 4 oxygen atoms which occupy the summits surrounding either 1 silicon atom or an aluminium atom placed in the center. Compensating cations (

sodium Sodium is a chemical element; it has Symbol (chemistry), symbol Na (from Neo-Latin ) and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 element, group 1 of the peri ...

potassium Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ...

) make the hole electrically neutral. The hole forms an assembly of small cells (or pores) of uniform and known size, in which a molecule of smaller size can be trapped by the phenomenon known as absorption. : To ensure the dehydration of the fresh natural flowers the mixture of

organic solvent A solvent (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for p ...

s is poured onto the hole until the level exceeds the level of the flowers by about 2 cm. The water molecules are progressively absorbed into the small cells or pores of the molecular sieve. : The receptacle is closed hermetically for a few days. : Once dried, the flower reabsorbs a little moisture of atmospheric origin, and this increases its suppleness and its plasticity. : As molecular sieve relates to the long-term preservation and treatment of

cut flowers Cut flowers are flowers and flower buds (often with some Plant stem, stem and leaf) that have been cut from the plant bearing it. It is removed from the plant for decorative use. Cut greens are leaves with or without stems added to the cut flow ...

for long duration, (i.e. continually maintaining their decorative properties ), Vermont Flowers has been using this method of preserving flowers instead of the traditional silica gel more than 20 years ago. The advantage was a much more professional regeneration of the molecular sieves. Flowers which are particularly suitable for such a treatment are roses, peonies,

camellia ''Camellia'' (pronounced or ) is a genus of flowering plants in the family Theaceae. They are found in tropical and subtropical areas in East Asia, eastern and South Asia, southern Asia, from the Himalayas east to Japan and Indonesia. There are ...

s, marigolds, globe flowers,

orchid Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Orchids are cosmopolitan plants that are found in almost every habitat on Eart ...

dahlia ''Dahlia'' ( , ) is a genus of bushy, tuberous, herbaceous perennial plants native to Mexico and Central America. Dahlias are members of the Asteraceae (synonym name: Compositae) family of dicotyledonous plants, its relatives include the sun ...

carnation ''Dianthus caryophyllus'' ( ), commonly known as carnation or clove pink, is a species of ''Dianthus'' native to the Mediterranean Basin, Mediterranean region. Its exact natural range is uncertain due to extensive cultivation over the last 2,00 ...

phlox ''Phlox'' (; "flame"; plural "phlox" or "phloxes", ) is a genus of 68 species of perennial and annual plants in the family Polemoniaceae. They are found mostly in North America (one in Siberia) in diverse habitats from alpine tundra to open ...

es, summer chrysanthemums,

hollyhock ''Alcea'' is a genus of over 80 species of flowering plants in the mallow family Malvaceae, commonly known as the hollyhocks. They are native to Asia and Europe. The single species of hollyhock from the Americas, the Iliamna rivularis, streamban ...

s, and the like, and other species with many petals or a fairly rigid structure.

Freeze drying

: Originally introduced in 1813 by

William Hyde Wollaston William Hyde Wollaston (; 6 August 1766 – 22 December 1828) was an English chemist and physicist who is famous for discovering the chemical elements palladium and rhodium. He also developed a way to process platinum ore into malleable i ...

to the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...

London London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...

, it was not until the late 80's the

freeze-drying Freeze drying, also known as lyophilization or cryodesiccation, is a low temperature Food drying, dehydration process that involves freezing the product and lowering pressure, thereby removing the ice by Sublimation (phase transition), sublimat ...

industry discovered the allurement and longevity of freeze-dried flowers. : Freeze dried flowers are fresh flowers that have been specially dried to preserve their natural shape and color. Freeze drying is accomplished by a process called sublimation. It requires a special freeze-drying machine. : It involves first freezing the flowers at 100K for at least 12 hours. A

vacuum pump A vacuum pump is a type of pump device that draws gas particles from a sealed volume in order to leave behind a partial vacuum. The first vacuum pump was invented in 1650 by Otto von Guericke, and was preceded by the suction pump, which dates to ...

slowly pulls the moisture out of the flowers as a vapor in one chamber, and then the vapor condenses as ice in another chamber. Because of this process, the shape and natural color of the flower is maintained. It has been found that certain flowers retain their color well despite the fact they have been freeze-dried. Apparently, such flowers retain their color due to the tissue composition of the petals, leaves, and the like. Carnations, African violets, roses,

asparagus Asparagus (''Asparagus officinalis'') is a perennial flowering plant species in the genus ''Asparagus (genus), Asparagus'' native to Eurasia. Widely cultivated as a vegetable crop, its young shoots are used as a spring vegetable. Description ...

and other

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

s, and baby's breath exhibit good color retention notwithstanding the

dehydration In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild deh ...

during the freeze-drying process. Those floral pieces which either dull or fade from dehydration may be given color by utilization of a florist's spray tint. This spray coloring restores the lost color which, in the sealed environment of the glass container of the final product, retains its given color along with the natural color of the other pieces.

Flower Press

: This floral preservation has its roots in Victorian times, but has also been brought into the current list of Floral Preservation because of new techniques of pressing, vacuum sealing and color enhancing. This method uses a "flower press" that sandwiches the flower between two rigid layers, often lined with a breathable/adsorbent fabric to allow moisture to leave the flower, then applies a small amount of pressure to the flower, allowing it to keep its shape while it dries. The art is then framed in a flat shadow box style frame, to hang on the wall. Vacuum sealing the art is recommended and the use of Museum Quality glass with a UV Factor of 97% to ensure the colors last.

Preservation in a resin pour

A resin pour preservation allows for flowers like roses to be preserved in a clear transparent mould, making this method a great choice for ornamental preservation of flowers. Two separate resin elements are mixed in equal proportions and poured into a silicone mould, often in an ice cube shape, with the flower inserted. With each pour, a heat gun is used to remove air bubbles that form at the surface of the pour. Those attempting a resin pour preservation are recommended to wear a respirator and gloves as a resin pour can give off fumes and also a considerable amount of heat. The preservation of real dried flowers can also be done within a bezel-based structure poured with resin.