Salvia rosmarinus, commonly known as rosemary, is a shrub with fragrant, evergreen, needle-like leaves and white, pink, purple, or blue flowers, native to the Mediterranean region. Until 2017, it was known by the scientific name Rosmarinus officinalis.
It is a member of the sage family Lamiaceae, which includes many other medicinal and culinary herbs. The name "rosemary" derives from Latin ros marinus (lit. 'dew of the sea'). Rosemary has a fibrous root system.
Rosemary (Salvia rosmarinus )
Rosemary is an aromatic evergreen shrub with leaves similar to hemlock needles. It is native to the Mediterranean region, but is reasonably hardy in cool climates. Special cultivars like 'Arp' can withstand winter temperatures down to about −20 °C (−4 °F). It can withstand droughts, surviving a severe lack of water for lengthy periods. It is considered a potentially invasive species and its seeds are often difficult to start, with a low germination rate and relatively slow growth, but the plant can live as long as 35 years.
Forms range from upright to trailing; the upright forms can reach 1.5 m (4 ft 11 in) tall, rarely 2 m (6 ft 7 in). The leaves are evergreen, 2–4 cm (3⁄4–1+1⁄2 in) long and 2–5 mm (1⁄16–3⁄16 in) broad, green above, and white below, with dense, short, woolly hair.
The plant flowers in spring and summer in temperate climates, but the plants can be in constant bloom in warm climates; flowers are white, pink, purple or deep blue. Rosemary also has a tendency to flower outside its normal flowering season; it has been known to flower as late as early December, and as early as mid-February (in the northern hemisphere).