Rose Usage

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.

The hybrid garden rose "Amber Flush"

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.

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.

Rose thorns are actually prickles - outgrowths of the epidermis.

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 prickles, 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.

Species

Further information: List of Rosa species

The genus Rosa is subdivided into four subgenera:

• 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.

    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).
    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.
    

    Perfume

     Rose oil, Attar of roses, and Rose water
    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.
    The main constituents of attar of roses are the fragrant alcohols geraniol and l-citronellol and rose camphor, an odorless solid composed of alkanes, which separates from rose oil.β-Damascenone is also a significant contributor to the scent.
    

    Food and drink

    Main article: Rose hip
    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.
    
    Rosa canina hips
    Rose petals or flower buds are sometimes used to flavour ordinary tea, or combined with other herbs to make tisanes.
    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.
    Rose flowers are used as food, also usually as flavouring or to add their scent to food.Other minor uses include candied rose petals.
    Rose creams (rose flavoured fondant covered in chocolate, often topped with a crystallised rose petal) are a traditional English confectionery widely available from numerous producers in the UK.