THE ROSE
A rose is a woody perennial of the genus Rosa, within the family Rosaseae. There are over 100 species. They form a group of erect shrubs, and climbing or trailing plants, with stems that are often armed with sharp prickles. Flowers are large and showy, in colours ranging from white through yellows and reds. Most species are native to Asia, with smaller numbers native to Europe, North America, and northwest Africa. Species, cultivars and hybrids are all widely grown for their beauty and fragrance. Rose plants range in size from compact, miniature roses, to climbers that can reach 7 meters in height. Different species hybridize easily, and this has been used in the development of the wide range of garden roses.
History Of The Rose
To appreciate the significance of roses as garden plants, it helps to
know a little of their extensive history. The early Romans were true
lovers of roses. They carpeted their floors and showered their guests
with rose petals, bathed in rose oils, drank rose wine, decorated
warriors with rose garlands and treated their sick with medications made
from rose petals and hips. When the supply of roses was not sufficient
to meet demands, they built heated greenhouses so they could have
flowers 12 months a year.
Evidence of the devotion given to the rose by early Christians is seen
in stained glass windows in hundreds of medieval churches throughout the
world. This tradition continues in modern churches today. Even the word
rosary, a series of prayers reliving the life of Christ, originally
meant rose garden. Throughout history, from writings by Confucius
several hundred years before the birth of Christ to England's War of the
Roses in the 15th century, roses have been a part of world events.
However, the roses that held such fascination long ago did not look much
like the modern hybrid teas and grandifloras most of us grow today. The
rose garden of Josephine, first wife of Napoleon, at Malmaison, their
home in France, is still in existence. This garden contained almost 250
different roses, mostly rose species and natural hybrids. Quite a number
of these roses are still in existence today, although they are not
widely distributed through commercial outlets.
The large collection of roses gathered by Josephine at Malmaison was an
important step in the development of today's modern roses. For the first
time, horticulturists could observe in one location the tremendous
diversity of the rose family. From the Orient came ever-blooming China
roses such as 'Parson's Pink China'. From Reunion, an island country in
the Indian Ocean, came the semi- double, pink Bourbon roses, which were
also ever-blooming. These were stunning in contrast to Europe's Gallica
roses, which, although extremely fragrant, bloomed only in early summer.
Even though rose breeding had been going on for centuries, many of the
roses displayed at Malmaison were natural hybrids and species found in
nature. Consequently, the true lineage of many roses is uncertain and
often confusing. Even still, horticulturists found the possibilities at
Malmaison exciting. They began creating their own crosses, changing rose
gardening forever. Hybrids between ever-blooming China roses and Rosa
moschata led to the Noisette roses. At the same time, the Hybrid
Perpetual was developed from mixed parentage. These were crossed with
Tea roses from China, resulting in the first hybrid tea rose. Soon, the
era of modern roses was in full swing.
In North America, roses were also making an impact. There are about 35
species of roses that are native to the United States. As far back as
the early 1600s, American Indians in the Northeast were planting roses
to add flower color to their villages. Many native American roses,
including Rosa californica, Rosa setigera and Rosa palustris, are rugged
plants that are supremely adapted to the climates of their origins. In
this current age of conservation when plants are required to thrive and
look attractive with a minimum of care, as well as reduced amounts of
water and fertilizer, these native American roses are ideal subjects.
In addition to native species, early settlers in North America also
introduced many roses originating from other parts of the world. In the
late 16th century, William Penn, founder of Pennsylvania, brought 18
rose plants from England to the new world. He later wrote a book for
pioneers about the value of roses as medicinal plants.
Today, roses are big business. The rose is the world's most popular
flower, and the national flower of the United States. Each year
commercial rose growers produce millions of plants that are sold
throughout the world. To meet the demand for new varieties, rose
hybridizing and variety testing continue as important parts of the
rose-growing process.
Botany
The leaves are borne alternately on the stem. In most species they are 5 to 15 centimetres (2.0 to 5.9 in) long, pinnate, with (3–) 5–9 (–13) leaflets and basal stipules; the leaflets usually have a serrated margin, and often a few small prickles on the underside of the stem. Most roses are deciduous but a few (particularly from South east Asia) are evergreen or nearly so.
Rose leaflets
The
flowers of most
species have five petals, with the exception of Rosa
sericea, which usually has only four. Each petal is divided into two
distinct lobes and is usually white or pink, though in a few species yellow or
red. Beneath the petals are five sepals (or in the case of some Rosa sericea,
four). These may be long enough to be visible when viewed from above and appear
as green points alternating with the rounded petals. There are multiple superior ovaries that develop into achenes.Roses are insect-pollinated in nature.
Exterior view of rose buds
The
aggregate
fruit of the rose is a berry-like structure called a rose hip.
Many of the domestic cultivars do not produce hips, as the flowers are so
tightly petalled that they do not provide access for pollination. The hips of
most species are red, but a few (e.g. Rosa pimpinellifolia) have dark purple to
black hips. Each hip comprises an outer fleshy layer, the hypanthium,
which contains 5–160 "seeds" (technically dry single-seeded fruits
called achenes)
embedded in a matrix of fine, but stiff, hairs. Rose hips of some species,
especially the Dog
Rose (Rosa canina) and Rugosa Rose
(Rosa rugosa), are very rich in vitamin C,
among the richest sources of any plant. The hips are eaten by fruit-eating birds such as thrushes
and waxwings,
which then disperse the seeds in their droppings. Some birds, particularly finches, also eat the
seeds.
Cross-section through a developing rose hip
While the sharp objects along a rose stem are
commonly called "thorns", they are technically prickles — outgrowths of the epidermis
(the outer layer of tissue of the stem). (True thorns, as produced by e.g. Citrus or Pyracantha,
are modified stems, which always originate at a node and which have nodes and
internodes along the length of the thorn itself.) Rose prickles are typically
sickle-shaped hooks, which aid the rose in hanging onto other vegetation when
growing over it. Some species such as Rosa rugosa
and Rosa pimpinellifolia have densely packed
straight spines, probably an adaptation to reduce browsing by animals, but also
possibly an adaptation to trap wind-blown sand and so reduce erosion and
protect their roots
(both of these species grow naturally on coastal sand dunes). Despite
the presence of prickles, roses are frequently browsed by deer. A few species of
roses have only vestigial prickles that have no points.
Rose thorns are actually prickles - outgrowths of the epidermis
Species
The genus Rosa is subdivided into four sub genera:
- Hulthemia (formerly Simplicifoliae, meaning "with single leaves") containing one or two species from southwest Asia, R. persica and Rosa berberifolia which are the only roses without compound leaves or stipules.
- Hesperrhodos (from the Greek for "western rose") contains Rosa minutifolia and Rosa stellata, from North America.
- Platyrhodon (from the Greek for "flaky rose", referring to flaky bark) with one species from east Asia, Rosa roxburghii.
- Rosa (the type subgenus) containing all the other roses. This subgenus is subdivided into 11 sections.
- Banksianae - white and yellow flowered roses from China.
- Bracteatae - three species, two from China and one from India.
- Caninae - pink and white flowered species from Asia, Europe and North Africa.
- Carolinae - white, pink, and bright pink flowered species all from North America.
- Chinensis - white, pink, yellow, red and mixed-color roses from China and Burma.
- Gallicanae - pink to crimson and striped flowered roses from western Asia and Europe.
- Gymnocarpae - one species in western North America (Rosa gymnocarpa), others in east Asia.
- Laevigatae - a single white flowered species from China
- Pimpinellifoliae - white, pink, bright yellow, mauve and striped roses from Asia and Europe.
- Rosa (syn. sect. Cinnamomeae) - white, pink, lilac, mulberry and red roses from everywhere but North Africa.
- Synstylae - white, pink, and crimson flowered roses from all areas.
Uses
Roses are best known as ornamental plants grown for their flowers in
the garden and sometimes indoors. They have been also used for
commercial perfumery and commercial cut flower crops. Some are used as
landscape plants, for hedging and for other utilitarian purposes such as
game cover and slope stabilization. They also have minor medicinal
uses.
Ornamental plants
The majority of ornamental roses are hybrids that were bred for their
flowers. A few, mostly species roses are grown for attractive or
scented foliage (such as Rosa glauca and Rosa rubiginosa), ornamental thorns (such as Rosa sericea) or for their showy fruit (such as Rosa moyesii).
Hybrid Tea cultivar 'Mrs. Herbert Stevens'
Ornamental roses have been cultivated for millennia, with the earliest known cultivation known to date from at least 500 BC in Mediterranean countries, Persia, and China. Many thousands of rose hybrids and cultivars have been bred and selected for garden use as flowering plants. Most are double-flowered with many or all of the stamens having mutated into additional petals.
In the early 19th century the Empress Josephine of France patronized the development of rose breeding at her gardens at Malmaison.
As long ago as 1840 a collection numbering over one thousand different
cultivars, varieties and species was possible when a rosarium was
planted by Loddiges nursery for Abney Park Cemetery, an early Victorian garden cemetery and arboretum in England.
A few species and hybrids are grown for non-floral ornamental use.
Among these are those grown for prominent hips, such as the flagon
shaped hips of Rosa moyesii. Sometimes even the thorns can be treated as an attraction or curiosity, such as with Rosa sericea.
Cut flowers
Bouquet of pink roses
Roses are a popular crop for both domestic and commercial cut flowers. Generally they are harvested and cut when in bud, and held in refrigerated conditions until ready for display at their point of sale.
In temperate climates, cut roses are often grown in glasshouses,
and in warmer countries they may also be grown under cover in order to
ensure that the flowers are not damaged by weather and that pests and
disease control can be carried out effectively. Significant quantities
are grown in some tropical countries, and these are shipped by air to
markets across the world.
Perfume
Rose perfumes are made from attar of roses or rose oil, which is a mixture of volatile essential oils obtained by steam distilling the crushed petals of roses. An associated product is rose water which is used for cooking, cosmetics, medicine and in religious practices. The production technique originated in Persia then spread through Arabia and India, and more recently into eastern Europe. In Bulgaria, Iran and Germany, damask roses (Rosa damascena 'Trigintipetala') are used. In other parts of the world Rosa centifolia
is commonly used. The oil is transparent pale yellow or yellow-grey in
colour. 'Rose Absolute' is solvent-extracted with hexane and produces a
darker oil, dark yellow to orange in colour. The weight of oil extracted
is about one three-thousandth to one six-thousandth of the weight of
the flowers; for example, about two thousand flowers are required to
produce one gram of oil.
Geraniol (C10H18O)
The main constituents of attar of roses are the fragrant alcohols geraniol and l-citronellol; and rose camphor, an odourless paraffin. β-Damascenone is also a significant contributor to the scent.
Rose water, made as a byproduct of rose oil production, is widely used in Asian and Middle Eastern cuisine.
Food and drink
Rose hips are occasionally made into jam, jelly, and marmalade, or are brewed for tea, primarily for their high vitamin C content. They are also pressed and filtered to make rose hip syrup. Rose hips are also used to produce Rose hip seed oil, which is used in skin products and some makeup products.[citation needed]
Rosa canina hips
Rose petals or flower buds are sometimes used to flavour ordinary tea. Sometimes they may be used as the sole plant material in herbal teas.
In France there is much use of rose syrup, most commonly made from an extract of rose petals. In the United States, this French rose syrup is used to make rose scones and marshmallows.[citation needed]
Occasionally rose flowers have been used as food, also usually as flavouring or to add their scent to food. Other minor uses include candied rose petals.
Medicine
The rose hip, usually from R. canina
is used as a minor source of Vitamin C. The fruits of many species have
significant levels of vitamins and have been used as a food supplement.
Many roses have been used in herbal and folk medicines. Rosa chinensis
has long been used in Chinese traditional medicine. This and other
species have been used for stomach problems, and are being investigated
for controlling cancer growth.
Culture
Art Roses are a favored subject in art and therefore used in various artistic disciplines. They appear in portraits, illustrations, on stamps, as ornaments or as architectural elements. The Luxembourg born Belgian artist and botanist Pierre-Joseph Redouté is known for his detailed watercolours of flowers, particularly roses.
Renoir's painting of cabbage roses, Roses in a vase
Henri Fantin-Latour
was also a prolific painter of still life, particularly flowers
including roses. The Rose 'Fantin-Latour' was named after the artist.
Other impressionists including Claude Monet, Paul Cézanne and Pierre-Auguste Renoir have paintings of roses among their works.
Symbolism
The long cultural history of the rose has led to it being used often as a symbol.
Pests and diseases
Wild roses are host plants for a number of pests and diseases. Many
of these are also shared with other plants, including especially other
genera of the Rosaceae.
Cultivated roses are often subject to severe damage from insect, arachnid and fungal pests and diseases. In many cases they cannot be usefully grown without regular treatment to control these problems.
