Plant Common Name
One of the oldest cultivated ornamentals, Rosa is a broad and complex genus with over 100 species and thousands of cultivated varieties. Roses are woody shrubs or rambling climbers that originate from Northwestern Africa, Asia, Europe and North America. They are either deciduous, evergreen or semi-evergreen, and all have stems lined with sharp woody thorns.
Roses have been grown for their beauty, food, perfume and medicine for nearly 5000 years. Early rose references and depictions go back as far as Ancient China, Mesopotamia, and Egypt. The Ancient Greeks and Romans venerated the rose and during the Crusades Europeans brought desirable eastern roses back to Europe. Rose cultivation hit a higher level of intensity in Victorian times and today scores of new, often patented, varieties are introduced each year.
Rose habit and size varies widely. They can be shrub forming, upright, climbing or scrambling and large or miniature. All have compound leaves that are most commonly glossy and dark to medium green, though some have burgundy and red hues or even fuzzy or waxy surface textures. Most lose their leaves each season, but some are evergreen.
Bloom time is variable. Most old cultivars of European heritage bloom with intensity for a short window of time in spring, summer or fall, depending on origin, whereas new cultivars tied to Asian rose lines are everblooming so long as growing conditions are favorable. Everyone is familiar with rose flowers. They are either single, semi-double or double and species, older varieties, and some new are characterized by a telltale spicy sweet fragrance. Single blooms have broad delicate petals and many pollen-topped filaments called stamens. Doubles and semi-doubles have numerous petals and may be flattened, fat and cabbage-like or tight and uniform. Flower color varies widely and comes in hues of red, orange, yellow, pink, lavender, white and coral with many bicolors. The fruit is a berry-like hip, which is edible, high in vitamin C and used for tea and sometimes compotes or jam. Rose-hips also provide important winter food to wildlife.
By and large, roses prefer full to partial sun, moderate temperatures and perfectly drained, slightly acid soil with average to good fertility. They often grow best in places with slightly dry climates, because such climates disfavor the fungal diseases that plague roses. For this reason, it is important to maintain good airflow within and between planted roses through good planting and pruning practices which will dissuade fungal attacks. Roses are rife with pest and disease problems. In fact, there are many common pests and diseases that can harm them. Fortunately, new cultivars are bred to be disease resistant. Hardiness is species dependent.
Roses are a landscape must—particularly newer disease resistant everblooming cultivars. Beyond landscape use, roses are used for perfume, medicine and food by cultures worldwide.
There are many groups of roses. Cultivated roses are characterized by numerous antique hybrids and modern hybrids.