thumb|upright=0.8|Flower, leaves and bulb of [[Hippeastrum miniatum. Francisco Manuel Blanco, Flora de Filipinas 1880–1883]]
thumb|upright=0.8|Hippeastrum bulb
thumb|upright=0.8|Detail of Hippeastrum flower
Hippeastrum () is a genus of 116 species, and over 600 hybrids and cultivars, of perennial, herbaceous and bulbous plants, native to tropical and subtropical regions of the Americas, from Mexico south to Argentina and on some islands in the Caribbean. The majority have large, fleshy bulbs and tall, broad, strap-like leaves that are (generally) evergreen, and large red or purple flowers. Numerous colors and cultivars have been created over the past hundred years.
Hippeastrum is a genus in the family Amaryllidaceae (subfamily Amaryllidoideae, tribe Hippeastreae, and subtribe Hippeastrinae). For many years, there has been confusion among botanists, as well as collectors and the general public, over the generic names Amaryllis and Hippeastrum; the former is a South African genus of plants, while the latter is a new world genus. However, the common name "amaryllis" has been used for Hippeastrum for years, especially for the ornamental cultivars (sold as indoor flowering bulbs around November and December, for Christmas, in the Northern Hemisphere). Within the genus Hippeastrum exist many epiphytic species, as well, which may be found living in natural debris and leaf litter on the crooks of tree branches; by comparison, Amaryllis is a primarily terrestrial, southern African genus of perennial bulbs.
Description
thumb|right|Hippeastrum striatum in cultivation
thumb|upright=0.8|Hippeastrum: Trivalvar [[Capsule (botany)|Capsule]]
thumb|upright=0.8|Hippeastrum: [[Pistil and stamens]]
thumb|upright=0.8|Hippeastrum: Stamens with filaments (white) ending in anthers carrying pollen
Most Hippeastrum bulbs are tunicate (a protective dry outer layer and fleshy concentric inner scales or leaf bases). The bulbs are generally between 5–12 cm (2"–5") in diameter and produce two to seven long-lasting evergreen or deciduous leaves that are 30–90 cm (12"–36") long and 2.5–5 cm (1"–2") wide. The leaves are hysteranthous (develop after flowering), sessile (borne directly from the stem or peduncle), rarely persistent and subpetiolate.
The flowers are arranged in umbelliform inflorescences which are pauciflor or pluriflor (2-14 flowers), supported on an erect hollow scape (flower stem) which is 20–75 cm (12"–30") tall and 2.5–5 cm (1"–2") in diameter with two free bracts forming a spathe which is bivalve with free leaflets at its base.
Depending on the species, there are two to fifteen large showy flowers, which are more or less zygomorphic and hermaphrodite. Each flower is 13–20 cm (5"–8") across, and the native species are usually purple or red. They are funnelform (funnel shaped)
Common name
Although the 1987 decision settled the question of the scientific name of the genus, the common name "amaryllis" continues to be used. Bulbs sold as amaryllis and described as ready to bloom for the holidays belong to the genus Hippeastrum. for example as Muscari subg. Leopoldia.)
Intergeneric hybrids
While interspecific hybrids of Hippeastrum are relatively common, hybridization with other genera of Amaryllidaceae are more rare. The most conspicuous exception is the hybrid obtained through crossbreeding with the Mexican Sprekelia formosissima (St James's lily, Aztec lily, Jacobean lily), another member of the tribe Hippeastreae, originally called Amaryllis formosissima, which is apomictic. × Hippeastrelia is the name given to this cross.-->
The cultivar 'Clown' (Double Galaxy Group) (white with red stripes) has received the Royal Horticultural Society's Award of Garden Merit.
Gallery
Uses
thumb|right|Hippeastrum 'Dancing Queen' flowering indoors in January
Cultivars of Hippeastrum are popular indoor ornamental plants prized for their large brightly colored flowers (including red, pink, salmon, orange and white). As such they have a very important place in the floriculture trade for sale as cut flowers or potted plants. Although the market is dominated by the Netherlands, and South Africa, other areas of production include Israel, Japan and the United States (Florida). Brazil also produces 17 million Hippeastrum bulbs annually.
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Bibliography
Books
General
- see also Hortus Veitchii, Messrs James Veitch and Sons
Historical sources (chronological)
- Digital edition by the University and State Library Düsseldorf
- (4 vols.)
Specific
Articles and theses
- For references to Hippeastrum, see pp. 7ff, 31–34; for detailed descriptions of Hippeastrum splendens, see pp. 52–53.
Gardening journals
Websites
Databases
- (Search for Hippeastrum)