Dendrobium bigibbum Lindley 1852 SECTION Phalaenanthe Photo courtesy of Nick Doe
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Common Name The Cooktown Orchid [Australia] - The Two-Humped Dendrobium
Flower Size 2" [5 cm]
An Australian and Papua and New Guinea [?], medium to large sized, epiphytic or lithophytic species that grows in semi-arid, low elevations below 1400 meters, in high light situations with cylindrical, narrow, tapering slightly towards both ends, green or reddish purple stems carrying 3 to 12, ovate or lanceolate, acute leaves held in the apical half and can bloom at any time of the year except for late spring with an axillary, to 12" [to 30 cm], arching raceme with 2 to 20, large, long lasting flowers that arise from the nodes near the apex of the leafed or not leafed canes if given a moderate winter rest and not resuming water until the new growths are 2 to 3" tall.
Synonyms Callista bigibba [Lindley]Kuntze 1891; Callista phalaenopsis (Fitzg.) Kuntze 1891; Callista sumneri [ F. Muell.] Kuntze 1891; Dendrobium biggibum [common mispelling], Dendrobium bigibbum subvar candidum [Rchb.f.] Veitch 1888; Dendrobium bigibbum var. album F.M.Bailey 1902; Dendrobium bigibbum var candidum Rchb.f. 1878; Dendrobium bigibbum var sumneri [F. Mueller]F.M.Bailey 1883; Dendrobium bigibbum var. superbum Rchb.f. 1878; Dendrobium lithocola D.L.Jones & M.A.Clem. 1989; Dendrobium phalaenopsis Fitzg. 1880; Dendrobium phalaenopsis var. compactum C.T.White 1941; Dendrobium phalaenopsis Fitz. var. statterianum Hort. ex Sander; Dendrobium sumneri F. Mueller 1867; Vappodes bigibba (Lindl.) M.A.Clem. & D.L.Jones 2002; Vappodes lithocola (D.L.Jones & M.A.Clem.) M.A.Clem. & D.L.Jones 2002
References W3 Tropicos, Kew Monocot list , IPNI ; Orchid Species Culture, Dendrobium Bakers 1996; Flora Malesiana Orchids of New Guinea Vol II Shuiteman and de Vogel 2002, The Dendrobiums Wood 2006
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Dendrobium bigibbum Lindley 1852 ssp. bigibbum
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Text by John Rees
Dendrobium bigibbum ssp. bigibbum grows on the western side of Cape York and has been commonly called the "Weipa Cooktown orchid" because it is found around Weipa, a bauxite mine on the western side of Cape York.
Its flowers are smaller than Den. bigibbum ssp. phalaenopsis and they grow to 5 cm across on canes of length similar to those of Den. bigibbum ssp. phalaenopsis. In flower, it is easily identified by the white spot on the labellum.
Dendrobium bigibbum Lindley 1852 ssp. compactum
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Text by John Rees
Dendrobium bigibbum ssp. compactum grows on rocks south of Laura to Cairns on the eastern side of Cape York. Because of the often exposed, harsh situations it grows in, it has evolved into a compact form with pseudobulbs about 25cm long.
Synonyms Dendrobium bigibbum var. compactum C.T.White 1941
Dendrobium bigibbum ssp. phalaenopsis
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Text by John Rees
Dendrobium bigibbum ssp. phalaenopsis grows between Mount Molloy and Cooktown on the eastern side of Cape York and is the original "Cooktown Orchid". It may have larger flowers (up to 7 cm across) than other varieties of the species. There are a number of cultivars of this including 'Albomarginatum' (with white margins on the petals and sepals) and 'Hololeucum' (white flowers). Pseudobulbs can grow to 1.2 m. Selective breeding has produced some much larger, paler and flatter flowers, so much so that judges at shows often question the validity of naming them Dendrobium bigibbum ssp. phalaenopsis
