AFRICAN

ORCHIDS

Read more of Cultivation of Erasanthe henrici (Schltr.) P.J.Cribb, Hermans & D.L.Roberts
Light:
1000-1500 fc. Plants should be grown in fairly low filtered or diffused light. Strong air movement should be provided at all times.
Temperatures:
Summer days average 83-85F (28-29C), and nights average 65-66F (18-19C), with a diurnal range of 17-20F (9-11C).
Humidity:
75-80% most of the year, dropping to 65-70% for about 3 months in spring.
Water:
Rainfall is moderate to very heavy from midspring to early autumn. Averages then decline rapidly resulting in a dry season that starts in late autumn and lasts into early spring. Cultivated plants should be watered heavily while actively growing, but drainage must be excellent and conditions around the roots should never be stale or soggy. Water should be reduced in autumn after new growths mature.
Fertilizer:
1/4–1/2 recommended strength, applied weekly when plants are actively growing. Many growers use a balanced fertilizer all year. Others, however, use a high-nitrogen fertilizer from spring to midsummer then switch to a high-phosphate formula in late summer and autumn.
Rest period:
Winter days average 73-75F (23-24C), and nights average 53-55F (12-13C), with a diurnal range of 19-22F (11-12C). Rainfall in the habitat is low for about 5 months from late autumn until the following spring, but moisture is available from very heavy dew and late-night mist during most of the dry season. Cultivated plants need less water in winter, particularly if they are being grown in the dark, short-day conditions common in temperate latitudes, but they should not be allowed to remain completely without water for long periods. Somewhat regular early-morning mistings between infrequent light waterings should provide sufficient moisture in most growing areas but still provide the necessary dry rest. Fertilizer should be reduced or eliminated until new growth starts and heavier watering is resumed in spring.
Growing media:
The pendulous inflorescences and the need for heavy watering and excellent drainage, suggests that Aeranthes henrici is most easily managed if mounted on a slab of tree-fern fiber. Mounted plants need high humidity, however, and during hot, dry weather they may need several waterings a day. If it is difficult to keep mounted plants moist enough, they may be grown in a shallow, perfectly drained hanging basket filled with a very open, fast-draining medium that has excellent drainage, is well aerated, and allows the medium to dry fairly rapidly after watering. Hillerman and Holst (1986) reported that all of their attempts to grow these plants in pots failed. Hawkes (1965) reported that for the genus in general, plants grown in containers grow best in tightly packed osmunda or shredded tree-fern fiber. Bechtel, Cribb, and Launert (1986) recommended mixing 6 parts fir bark, 1 part perlite or pumice, 1 part of coarse peat, and 1 part of charcoal. These plants rot easily if conditions at the roots are stale, so they should be repotted before the medium starts to break down. Repotting is best done just as new roots start to grow which enables the plant to become reestablished in the shortest possible time.
Miscellaneous notes:
In the habitat, however, these plants flower in autumn. Hillerman and Holst (1986) reported that they have found this species difficult to grow even when mounted.
References:
This information is quoted from a Charles and Margaret Baker culture sheet, with permission from Troy Meyers This email address is being protected from spambots. You need JavaScript enabled to view it.. The entire culture sheet can be obtained by subscription from Orchid Species Culture, http://orchidculture.com
Bechtel, H., P. Cribb, and E. Launert. 1980. Manual of cultivated orchid species. MIT Press, Cambridge, Mass. Hamilton, R. 1988. When does it flower? 2nd ed. Robert M. Hamilton, 9211 Beckwith Road, Richmond, B. C., Canada V6X 1V7. Hawkes, A. [1965] 1987. Encyclopaedia of cultivated orchids. Faber and Faber, London. Hillerman, F. and A. Holst. 1986. An introduction to the cultivated Angraecoid orchids of Madagascar. Timber Press, Portland, Ore. Pridgeon, A. ed. 1992. The illustrated encyclopedia of orchids. Timber Press, Portland, OR.
Photos/drawings:
Hillerman, F. and A. Holst. 1986. An introduction to the cultivated Angraecoid orchids of Madagascar. Timber Press, Portland, Ore. (Color photo) Pridgeon, A. ed. 1992. The illustrated encyclopedia of orchids. Timber Press, Portland, OR. (Color photo)











Erasanthe henrici (Schltr.) P.J.Cribb, Hermans & D.L.Roberts, Adansonia, III, 29: 28 (2007).
Homotypic Synonyms:
Aeranthes henrici Schltr., Repert. Spec. Nov. Regni Veg. Beih. 33: 278 (1925).
Description:
Plants heavy, acaulis or with a thick stem (15 mm in diameter) but very short with the roots thick (6- 7 cm): leaves 4-6 lingutate (9-23 x 1.6-5.5 cm), coriaceous and with the margins often undulate. Inflorescence pendent, 12-40 cm long; peduncle 6-15 cm, with 2-3 sheaths which are shorter than the internodes; 3-6 flowered, flowers pure white, very large; bracts oval-obtuse, generally 15 mm long equal to one-third the length of the pedicel. Sepals lanceolate, elongated in a filiment, 11 cm long generally, the lateral with their front margins slightly enlarged above the base. Petals lanceolate, elongated in a filiment to a total length of about 9 cm. Labellum to alt of 10cm long, the limbus very wide (3.8 cm) above the base, ciliate- fimbriate marginally, elongated in front by a linguiform lamina, truncate apically and tipped by a long setifomi-filiform acumin (6 cm long). Foot in a very wide funnel, elongated with a filiform-cylindrical spur, 6 cm. long. Column 8 mm tall. Pedicel generally 4 cm long. Capsule longly (3 cm), 4 pedicellate, narrowly elliptical (7 x 1.5 cm), attenuate toward both ends, with the dorsal angles 3 winged and slightly more projecting than the ends.
Habitat:
This orchid is found in a rather narrow range in windswept locations at about 3300 ft. (1000 m). It grows on trees in the humid forests of central Madagascar. Flowers in April.
Cultivation:
Read more of Cultivation of Erasanthe henrici (Schltr.) P.J.Cribb, Hermans & D.L.Roberts
Distribution:
Madagascar
References:
Manual of Orchids Stewart 1995; An Introduction to the Cultivated Angraecoid Orchids of Madagascar Hillerman & Holst 1986; Manual of Cultivated Orchids Bechtel, Cribb, Laurent 1992; The Illustrated Encyclopedia of Orchds Pridgeon 1992; Flora of Madagascar Perrier 1981; AOS Bulletin Vol 67 No 2 1998; AOS Bulletin Vol 75 No 8 2006; Orchids Australia Vol 10 No 4 1998; Angraecoid Orchids Stewart, Hermans, Campbell 2006; Orchids of Madagascar Hermans 2007; Field Guide to the Orchids of Madagascar Cribb & Herman 2009 ; WCSP (2017). 'World Checklist of Selected Plant Families. 27.02-2017; http://apps.kew.org/wcsp/
Images:
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In culture In culture In culture In culture
Erasanthe henrici 01 Erasanthe henrici  02 Erasanthe henrici  03 Erasanthe henrici  04
Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission.

Habitat/In situ Habitat/In situ Habitat/In situ
Erasanthe henrici  01 Erasanthe henrici 03 Erasanthe henrici  in situ
Photograph© Olaf Pronk. Image used with kind permission. Photograph© Olaf Pronk. Image used with kind permission. Photograph© Olaf Pronk. Image used with kind permission.












Erasanthe henrici subsp. isaloensis P.J.Cribb, Hermans & D.L.Roberts, Adansonia, III, 29: 30 (2007).
Heterotypic Synonyms:
Aeranthes henrici var. isaloensis H.Perrier ex Hermans, Orchids Madagascar, ed. 2: 287 (2007).
Description:
Differing from the type by the bracts which are triangular-acute; the flowers smaller (m. sep. 7.5 cm.; lat. seps. 7.5 cm: pets. 6.3 cm.; lab. 6 cm.) and of a white flushed with greenish; the labellum with its basal lamina elliptical-transverse (35 x 42 mm) elongated by a (10 x 10 mm) square lamina and a shorter (15 mm) acumin: the column longer (10 mm); the spur (11-12cm) and the pedicel (30-32 mm.) shorter. Other difference are found in the column which is provided with a tooth on its lower front, forming a projection in the spur oriface; the anther 6 mm wide with its front margins heavily indented and shaded with brown: the pollina are large (3.5 x 2 mm) and oval: the cauda (2 mm) are enlarged and angular-twisted; the viscidiums blackish, and the lobes of the rostellum forming 2 angular and conntigious teeth 4 mm. long.
Habitat:
Epiphyte, forests in sandstone areas from 900 m. alt.; flowering: March.
Cultivation:
As given for the genus.
Distribution:
N. Madagascar
References:
WCSP (2017). 'World Checklist of Selected Plant Families. 27.02-2017; http://apps.kew.org/wcsp/
Images:
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Erasanthe henrici subsp. henrici.
Description:
Flowers large, dorsal sepal up to 11 spur 16 cm long.
Habitat:
Epiphyte in humid evergreen forest 750-1000 m; flowering in April.
Cultivation:
As given for the genus.
Distribution:
N. & NC. Madagascar
References:
WCSP (2017). 'World Checklist of Selected Plant Families. 27.02-2017; http://apps.kew.org/wcsp/
Images:
Click on each image to see a larger version.