Angraecum

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Angraecum

Angraecum sesquipedale habitus
Note extremely long spurs of flowers

Scientific classification

Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Liliopsida
Order:	Asparagales
Family:	Orchidaceae
Subfamily:	Higher Epidendroideae
Tribe:	Vandaeae
Subtribe:	Angraecinae
Alliance:	Angraecum
Genus:	Angraecum Bory, 1804

Selected Species

Angraecum eburneum
Angraecum leonis - Lion's Moustache Orchid
Angraecum magdalenae - Queen of the Angraecums
Angraecum sesquipedale - Star of Bethlehem Orchid

See List of Angraecum species for complete list.

Synonyms

Aerobion Kaempf. ex Spreng.
Angorchis Thouars
Bonniera Cordem.
Ctenorchis K. Schum.
Lepervenchea Cordem.
Macroplectrum Pfitzer
Monixus Finet
Pectinaria Cordem.

The genus Angraecum, abbreviated as Angcm in horticultural trade, common name Angrec or Comet Orchid, contains about 220 species, some of them among most magnificent of all orchids. They are quite varied vegetatively and florally and are adapted to dry tropical woodland habitat and have quite fleshy leaves as a consequence. Most are epiphytes, but a few are lithophytes.

Tropical Africa and Madagascar contain the majority of the genus with outlying species in southeast Asia. But these orchids can also be found on the Comoros, the Seychelles, and the Mascarenes. They occur between sea level and 2,000 m in humid regions.

The long-lasting flowers are racemose and grow from the leaf axils. They are mostly white, but a few are yellow, green or ochre. They all have a long spur at the back of the labellum (lip).

In the case of Angraecum sesquipedale, a species from Madagascar, on observing the 30cm spur in the lip, Charles Darwin made the hypothesis that, since the nectar was at the bottom of the spur, a pollinator must exist with a tongue at least that long. Otherwise the orchid could never be pollinated. At the time, he was not believed. However, in 1903, the predicted pollinator was discovered, a hawk moth then named Xanthopan morganii praedicta ("praedicta" meaning "the predicted one"). It has an appropriately long proboscis. The specific name sesquipedale means "one foot and a half", referring to the length of the spur. This is a perfect example of mutual dependence of an orchid and a specific pollinator.

[edit] Growing Angraecums

Much like all other orchids, no need for special care or attention. Like all other orchids best to water in the mornings as to avoid fungal rot due to overnight dampness. Feeding as per other orchids and similar light conditions: in humid and hot regions (sub tropical) feed fortnightly during growing season (Summer) with a certified orchid fertiliser following directions on packet, weaker solutions are also okay if you're worried. In summer water weekly or more depending on situation. Angraecums flower best when in a lighter position. NOT FULL SUN - KEEP OUT OF DIRECT SUNLIGHT as this can damage (and eventually kill) your plant. Most Angraecums will have their leaves for a number of years so any sun burn spots are ugly for a significant period and also may expose your plant to disease. In indirect sunlight your Angraecums will reward you with blooms and attractive growth.

Angraecum Veitchii: HIGHLY RECOMMENDED - a very rewarding orchid. In indirect light and watered/fed regularly this plant will produce blooms annually (usually in Late Winter to Spring - for Australia this occurs in August - excellent for those wanting to show their plants at Brisbane's Ekka! You will notice a few lovely specimens there in the Gardening Exhibits). The flowers last a while if kept in a sheltered position and their strong heady fragrance is delightful. They only release their perfume at night. Flowers are large (4 - 9 cm across), waxy, white to greenish cream in colour and borne on stems of seven to ten depending on the faithfulness of your fertilising, watering, and indirect light provision. The leaves are large, thick straps that alternately fan out from a central (monopodal) stem. Pups (keikis) form at the base of the stem and can either be divided from the parent plant once they have at least three roots of their own or alternatively, left on the plant these will make a stunning specimen as when mature will produce blooms with the parent plant - many award winning angraecum veitchiis are grown as such. In the right conditions these orchids are healthy and require little attention. As they are epiphites the potting mixture should be loose and free draining. Prolific roots are formed from the base and also amongst the lower half of the foliage. These are attractive although somewhat troublesome when moving plants to and from shows. Once your angraecum is big it is best to pot it in a heavy terracotta pot or place a brick in the bottom of the pot in order to ensure your beauty does not get top heavy and risk snapping when blown over in the wind (especially since they flower during the windier times of the year, this can be very sad). When watering a good soaking with a hose or watering-can is best (not just a misting from a spray gun) as this helps to flush away any salts from fertilisers that may be present in the potting mixture and also thoroughly wets the plant. Make sure the roots halfway up the stem get a soaking too, not just the potted roots. This is a great orchid and will give you years of pleasure. They're slow growing and require little attention. Very hard to kill.