Rose gardening is a past time and is enjoyable by people from all walks of life, of all ages, from all backgrounds and religions.
A rose is a flowering shrub of the genus Rosa and the flower of this shrub. There are more than a hundred species of wild roses, all from the northern hemisphere and are generraly from temperate regions.
The species form a group of generally thorny shrubs or climbers, and sometimes trailing plants, usually reaching 2-5 m tall. They sometimes reach as high as 20 m by climbing over other plants.
The leaves of most species are 5-15 cm long, and the leaflets usually have a serrated margin. Often a few small thorns exist on the underside of the stem. The majority of roses are deciduous, but a few (notably in southeast Asia) are evergreen or nearly so.
The flowers have five petals (with the exception of Rosa sericea which often has only four), usually white or pink, and in a few species - yellow or red. The ovary is inferior, developing below the petals and sepals.
The fruit of the rose is a berry-like structure called a rose hip. The rose species that produce open-faced flowers are attractive to pollinating bees and other insects, and thus more apt to produce hips. Many of the domestic cultivars are so tightly petalled that they do not even provide access for pollination. The hips of most species are red, but a few such as Rosa pimpinellifolia have dark purple to black hips.
Each hip comprises an outer fleshy layer, and inside containing 5-25 seeds (technically achenes) embedded into a kind of matrix of fine, but stiff, hairs. Rose hips of some species, especially the Dog Rose (Rosa canina) and Rugosa Rose (Rosa rugosa), and are extremely rich in vitamin C. They are 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 such as finches also eat the seeds.
Most roses have thorns or prickles. The thorns are usually sickle-shaped hooks, which help the rose in hanging onto other vegetation when growing over it. Some species such as Rosa rugosa and Rosa Pimpinellifolia instead have densely packed straight spines (probably an adaptation to reduce browsing by animals) but also possibly an adaptation to trap wind-blown sand in an effort to reduce erosion and protect their roots (as both of these two species grow naturally on coastal sand dunes). Despite the presence of these thorns, roses are frequently browsed by deer. A few species of roses have vestigial thorns that have no points.
Roses are subject to several diseases. The most serious is rose rust (Phragmidium mucronatum), a type of Rust fungus, which can defoliate the plant. More common, though less debilitating, are rose black spot, caused by the fungus called Diplocarpon rosae, which makes circular black spots on the leaves in summer, and rose mildew, which is caused by Sphaerotheca pannosa. Roses are also used as food plants by the larvae of some Lepidoptera species.
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