Plant Taxonomy of Hollyhock Plants:
Plant taxonomy classifies hollyhocks as Alcea rosea. Sometimes, the genus name is given as Althea; but don't confuse the plant with rose of sharon, which may also go by that name. Among the more popular types are the black hollyhocks ('nigra' cultivar), plants with such dark flowers as to be almost truly black in color.
Most are either biennial plants or short-lived herbaceous (although the dead flower stalks persist through winter) perennial plants. The popular 'Zebrina' is an annual plant.
Hollyhock plants are typically tall (6 feet or more in height), slender plants. Some types have handsome double or semi-double flowers; the flowers come in a wide variety of colors. The texture of the leaves is coarse.
Planting Zones for Hollyhock Plants:
Alcea, a plant indigenous to China, may be grown in planting zones 4-10 (or even lower, depending on variety).
Sun and Soil Requirements:
Uses for Hollyhock Plants:
What plants come to mind when you hear, "cottage gardens?" There's a good chance that hollyhocks will be one of the plants you think of. A classic look is hollyhock plants lining a picket fence. Because they are tall plants, they can be a good choice for the back rows of planting beds.
Make sure that your hollyhocks have good air circulation. Otherwise, you may lose them to hollyhock rust, a fungus (Puccinia malvacearum). Insect pests for hollyhocks include whitefly (you can try spraying with neem oil, although I myself didn't have much success). You can deadhead hollyhocks to promote better flowering, although some growers sacrifice flowers in exchange for re-seeding. Since hollyhocks are tall plants, staking may be advisable, especially in windy areas.
Wildlife Attracted to Hollyhock Plants:
Hollyhocks are known to be plants that attract butterflies and bees. They are also good hummingbird plants.
Meaning of Names, "Hollyhocks," "Alcea":
According to The English Cottage Garden Nursery, Alcea "comes from the Greek 'alkaia', meaning Mallow." The same source suggests the possibility that the name, "hollyhock" is "a corruption of 'holy' - the plant was alleged to have been brought back here [i.e., to England -- ed.] with the Crusades. It may also have been called Hock Leaf because it was used to reduce the swelling in horses' hocks." Maltese cross is also thought to have been brought to Europe from the East during the Crusades.