Read more of Cultivation of Plectrelminthus caudatus (Lindl.) Summerh.
Light:
2000-3000 fc. Light should be filtered or diffused, and plants should not be exposed to direct midday sun. Strong air movement should be provided at all times.
Temperatures:
Summer days average 85-86F (29-30C), and nights average 68F (20C), with a diurnal range of 17-18F (9-10C).
Humidity:
80–85% most of the year, dropping to near 75% for about 2 months in late winter and early spring.
Water:
Rainfall in the habitat is heavy most of the year, with 2–3 rather dry months in winter. Cultivated plants should be watered heavily while actively growing. Water should be reduced somewhat in late autumn.
Fertilizer:
1/4–1/2 recommended strength, applied weekly when plants are actively growing. Many growers prefer to use a balanced fertilizer throughout the year; but others use a high-nitrogen fertilizer from spring to midsummer, then switch to one high in phosphates in late summer and autumn.
Rest period:
Winter days average 81-83F (27-28C), and nights average 64-66F (18-19C), with a diurnal range of 17-18F (9-10C). Growers report that plants will grow a few degrees cooler in intermediate conditions, but seem to grow better under warmer conditions. Rainfall in the region is lower in winter. In addition to the rainfall, however, moisture from heavy dew and late-night mist often is available to the plants, and this moisture is not reflected in the rainfall averages. Cultivated plants need less in winter, but they should never dry out completely or remain without water for long periods. In most growing areas, somewhat regular early-morning mistings between occasional light waterings should provide the dry rest without letting the plant become too dry. Fertilizer should be reduced or eliminated when water is reduced.
Growing media:
With its very long roots, this plant is probably best grown in a basket that is 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. Growers generally use medium-sized fir bark or shredded tree-fern fiber and add varying amounts of chunky perlite and/or chopped sphagnum moss to keep the medium open and retain some moisture. Including charcoal in the mix also holds the medium open and prevents souring in the pot. Repotting should be done just as new roots start to grow. This enables the plant to become reestablished in the shortest possible time.
References:
This information is quoted from a Charles and Margaret Baker culture sheet, with permission from Troy Meyers
Genus Plectrelminthus
A key to the genus Plectrelminthus Raf.
| 1.a | Stem rather short, rarely up to 15 cm. long; leaves closely imbricate at base, oblong or elliptical-oblong, almost equally bilobed at apex with rounded lobes, 10-30 cm. long, 1.5-3.5 cm. broad; inflorescence 25-60 cm. long, 4-10-flowered; sepals and petals lanceolate-linear, acuminate, the former 3.5-5 cm. long; lip about as long as the sepals, 1-2.5 cm. broad in the middle; spur 17-25 cm. long, spirally twisted. | Plectrelminthus caudatus |
World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/monocots/ accessed 12/03/2017
Plectrelminthus caudatus var. trilobatus Szlach. & Olszewski, in Fl. Cameroun 36: 828 (2001).
Description:
Differs from the type in having 2 extra lobes on the lip on either side of the apex below the acumen.
Habitat:
Distribution:
WC. Trop. Africa
Plectrelminthus caudatus (Lindl.) Summerh., Kew Bull. 4: 441 (1949).
Homotypic Synonyms:
Angraecum caudatum Lindl., Edwards's Bot. Reg. 22: t. 1844 (1836).
Listrostachys caudata (Lindl.) Rchb.f. in W.G.Walpers, Ann. Bot. Syst. 6: 907 (1864).
Angorchis caudata (Lindl.) Kuntze, Revis. Gen. Pl. 2: 651 (1891).
Leptocentrum caudatum (Lindl.) Schltr., Orchideen Beschreib. Kult. Zücht.: 600 (1914).
Description:
A robust monopodial epiphyte with leafy stems up to 6 in. (15 cm) long. The roots are long and stout, sometimes almost 0.4 in. (1 cm) in diameter. Pseudobulb/stem: Up to 6 in. (15 cm) long. The lower part of the stem is enclosed by the overlapping bases of old leaves that have fallen. Leaves: 4-12 in. (10-30 cm) long by 0.6-1.4 in. (1.5-3.5 cm) wide. Several overlapping, longitudinally folded leaves are set close together and carried at the apex of the stem. They are broadly strap-shaped and unequally and bluntly bilobed at the apex. Inflorescence: 14-31 in. (35-80 cm) long. The flower spike emerges from the axils of the lower leaves and may be spreading or pendulous. Flowers are carried on a zigzag rachis on the upper part of the spike. The pedicel and ovary are twisted so that the flowers are held in positions parallel to the rachis, with the tip pointing toward the base of the plant. Flowers: 4-10 per inflorescence. The rather cup-shaped flowers have yellow-green sepals and petals that may sometimes be flushed with bronze. The lip is white. Sepals and petals are oblong and have sharply pointed tips. The dorsal sepal is 1.2-2.0 in. (3-5 cm) long by 0.2-0.3 in. (0.5-0.7 cm) wide. The lateral sepals are slightly narrower and are joined at the base under the spur. Petals are 1.2-1.4 in. (3.0-3.5 cm) long by 0.2 in. (0.4-0.5 cm) wide. The lip is 1.4-2.0 in. (3.5-5.0 cm) long by 0.4-1.0 in. (1.0-2.5 cm) wide. It is egg-shaped with a wavy edge, has a caudate apex, and has a long basal claw with two projections that almost meet to form a V. The spur at the base of the flower is thick, pendent, flexuous, and 6-10 in. (15-25 cm) long, are in. ( cm) across.
Habitat:
Plants grow as epiphytes in forests, but in positions where they receive strong light. With as many reported collections as there have been, it seems strange that not a single one included habitat elevation, but that is exactly what I have encountered. La Croix & La Croix (1997) report that these plants will grow under intermediate conditions, but are difficult to flower and performs better in warm temperatures.
Cultivation:
Read more of Cultivation of Plectrelminthus caudatus (Lindl.) Summerh.
Distribution:
W. & WC. Trop. Africa
Two variants are approved by the World Checklist of monocotyledons.
| Plectrelminthus caudatus var. caudatus | W. & WC. Trop. Africa. |
| Plectrelminthus caudatus var. trilobatus Szlach. & Olszewski | C. Trop. Africa. |
References:
Hutchinson, J., and J. Dalziel, ed. 1968. Flora of west tropical Africa, vol. 3—part 1. Royal Botanic Gardens, Kew. la Croix, I. and E. la Croix. 1997. African orchids in the wild and in cultivation. Timber Press, Portland, OR.; WCSP (2017). 'World Checklist of Selected Plant Families. 12.03.2017; http://apps.kew.org/wcsp/
Images:
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| In culture | In culture | In culture | In culture | In culture | In culture |
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| Photograph ©Leo Klemm. Image used with kind permission | Photograph ©Leo Klemm. Image used with kind permission | Photograph ©Leo Klemm. Image used with kind permission | Photograph ©Leo Klemm. Image used with kind permission | Photograph ©Leo Klemm. Image used with kind permission | Photograph ©Leo Klemm. Image used with kind permission |
