Winter-hardy hibiscuses are herbaceous perennials in the mallow (Malvaceae) family that belong to six species native to the United States: H. coccineus Walter (scarlet rose mallow), H. dasycalyx S.F Blake and Shiller (Neches River rose mallow), H. grandiflorus Michx. (swamp rose mallow), H. laevis All. (halberdleaf rose mallow), H. lasiocarpos Cav. (hairy-seeded rose mallow), and H. moscheutos L. (crimsoneyed rose mallow) (Lawton, 2004; Winters, 1970). All species in the winter-hardy hibiscus group have the same complement of chromosomes (2n = 38) (Klips, 1995) and hybridize relatively easily. They grow naturally in marshy habitats in the eastern part of the United States to southern Ontario (Canada) and in California (H. lasiocarpos).
Winter-hardy hibiscuses, especially H. moscheutos and its hybrids, have attractive, tropical-looking flowers with a size of 5 to 30 cm in diameter. Winter-hardy hibiscus species are long-day plants (Warner and Erwin, 2001). All species of winter-hardy hibiscus are long-day plants (Warner and Erwin, 2001) that abundantly produce flowers from midsummer through late fall. The flowers last 1 d and colors range from white through pink to red, depending on the species. Recently developed cultivars of H. moscheutos such as ‘Fantasia’ (PP11,853) and ‘Plum Crazy’ (PP11,854) have lavender flowers. Breeders have also developed cultivars with different leaf shapes and colors and varying plant architecture. ‘Blue Angel’ has been released to provide a cultivar with a unique violet–blue flower color, which is not reported for winter-hardy hibiscus species.
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FlemingD.W.ZwetzigG.A.2003Hibiscus plant named ‘Fireball’. U.S. Patent and Trademark Office. 28 Nov. 2011. <http://patft.uspto.gov>.
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WestT.P.PreeceJ.E.2004Effects of thidiazuron and nutrient salt formulations on micropropagation of hardy hibiscus (Hibiscus moscheutos L.)Acta Hort.630293297