Alcea rosea (common hollyhock) is an ornamental plant in the Malvaceae family. It was imported into Europe from southwestern China during, or possibly before, the 15th century. William Turner, a herbalist of the time, gave it the name "holyoke" from which the English name derives.
Althaea rosea is variously described as a biennial (having a two-year life cycle), as an annual, or as a short-lived perennial. It frequently self-sows, which may create a perception that the plants are perennial. The plant may flower during its first year when sown early. It will grow in a wide range of soils, and can easily reach a height of about 8 feet (2.4 m).
The flowers are a range of colours from white to dark red, including pink, yellow and orange. Different colours prefer different soils. The darker red variety seems to favour sandy soils, while the lighter colour seems to favour clay soils. The plants are easily grown from seed, and readily self-seed. However, tender plants, whether young from seed or from old stock, may be wiped out by slugs and snails. The foliage is subject to attack from rust (Puccinia malvacearum), which may be treated with fungicides. Commercial growers have reported that some closely related species (Althaea rugosa and Althaea ficifolia) are resistant to this fungus.
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