viridifolia. The cross is known as Gerbera × hybrida. Thousands of cultivars exist. They vary greatly in shape and size. Colours include white, yellow, orange, red, and pink. The centre of the flower is sometimes black. Often the same flower can have petals of several different colours. The flower-heads (capitula) can be as small as 7 cm (Gerbera 'mini Harley') in diameter or up to 12 cm (Gerbera ‘Golden Serena’). Gerbera is also important commercially. It is the fifth most used cut flower in the world (after rose, carnation, chrysanthemum, and tulip). It is also used as a model organism in studying flower formation. Gerbera contains naturally occurring coumarin derivatives. It is attractive to bees, butterflies, and birds, but resistant to deer. Small ones are called gerbrinis. References Sources Hansen, Hans V. A taxonomic revision of the genus Gerbera (Compositae, Mutisieae) sections Gerbera, Parva, Piloselloides (in Africa), and Lasiopus (Opera botanica. No. 78; 1985), . Nesom, G .L. 2004. Response to "The Gerbera complex (Asteraceae, Mutisieae): to split or not to split" by Liliana Katinas. Sida 21:941–942. Bremer K. 1994: Asteraceae: cladistics and classification. Timber Press: Portland, Oregon. External links Gerbera.org—official website of the Gerbera Association—established in Barberton, South Africa Traugott-Gerber-Museum, Germany (German) Asteraceae genera Garden plants Mutisieae