About Alcea rosea L.
Alcea rosea L., commonly known as common hollyhock, is an ornamental dicot flowering plant that belongs to the family Malvaceae. It was brought into Europe from southwestern China during the 15th century, or potentially even earlier. William Turner, a herbalist working in that period, named the plant "holyoke", which is the origin of its modern English name. In the Americas, the flowers of this plant attract both hummingbirds and butterflies. Alcea rosea has been described variously as a biennial with a two-year life cycle, an annual, or a short-lived perennial. It often self-sows freely, which can lead to the perception that individual plants are long-lived perennials. If sown early, the plant can produce flowers during its first year of growth. It can grow successfully in a wide range of soil types and can easily reach a height of 2.4 m (8 ft). Its flowers come in a range of colors from white to dark red, and also include pink, yellow, and orange. Different colored varieties have different soil preferences: darker red varieties appear to favor sandy soils, while lighter colored varieties favor clay soils. Alcea rosea is easy to grow from seed, and self-seeds readily. Young tender plants, whether newly grown from seed or produced from older established stock, can be completely killed by slugs and snails. Its foliage is often attacked by rust fungus, which can be treated with fungicides. Commercial growers have noted that two closely related species, Alcea ficifolia and A. rugosa, are resistant to this rust fungus.
