AFRICAN

ORCHIDS

Aeranthes unciformis P.J.Cribb & Nusb., Candollea 67: 272 (2012).
Description:
An epiphyte herb on trees with a very short stem; roots adventitious, slender, 1-1.5 mm in diameter. Leaves 4-5, distichous, twisted at the base to lie in one plane, oblanceolate oblong, obtusely obliquely bilobed at the tip mostly with a longer distal lobe and a shorter proximal lobe, 6-8 x 0.9-2 cm, articulated at the base to a short conduplicate leaf base. Inflorescences much shorter than the leaves, axillary, 1- to 3- flowered, 25-30 mm long; peduncle terete, 10-12 mm long; bracts small, ovate, acuminate, 4-4.5 mm long. Flower resupinate, large for the size of the plant, translucent, white; pedicle and ovary 20 mm long, scabrid. Dorsal sepal curving forwards over the column and lip, linear-tapering, longly caudate, 65-85 x 3 mm; lateral sepals spreading-decurved, falcate at base, linear-tapering, longly caudate, 55-60 x 4.5-5 mm. Petals spreading upwards, linear-tapering, caudate, 29-30 x 5-6 mm. Lip ecallose, somewhat porrect, concave, broadly ovate, caudate, ciliate along the margin of the tapering part, 38-50 x 20- 22 mm; spur with a broad mouth then narrowly cylindrical, straight, 22-24 mm long. Column 5 mm long, with two recurved lateral arms at the tip, each 2 mm long; anther cap broadly cordiform; viscidia 2, strap-like, 2 mm long.
Etymology:
The specific epithet refers to the morphology of the dorsal sepal curving forwards over the column and lip.
Notes:
Aeranthes unciformis is very distinct in the genus. It has the habit of A. laxiflora Schltr., a widespread species in the Mountains of Madagascar, but quite different and much larger flowers. Its flowers are somewhat reminiscent of those of A. caudata Rolfe but much larger with longer acumens and are borne two or three at a time in a short inflorescence, rather than appearing in succession on slender elongate wiry branching peduncles. The lip is very distinctive, almost transversely elliptic at the base then drawn out and tapering into a long acumen at the tip. The spur, 22-24 mm long, is also much longer than in most Aeranthes species. The dorsal sepal is very peculiar, curving forwards over the column and lip.
Habitat and ecology:
Aeranthes unciformis was recorded in dry deciduous forest close to a seasonal river at 170 m elevation. This epiphytic plant occurs on trunks of trees at 2 to 4 m above ground. It grows in forests with canopies reaching 8 to 12 m, with emergent trees reaching 14 m, with an shrub stratum at 3 to 5 m high, and a sparse suffrutescent stratum less than 0.5 m high. Flowering time. – February.
Cultivation:
As given for the genus.
Distribution:
The species is only known from the type locality in the northern part of the Bekaraoka forest in the Loky-Manambato region in North-East Madagascar.
References:
Angraecum Darainense P. J. Cribb & Nusb. and Aeranthes Unciformis P. J. Cribb & Nusb. (Orchidaceae), Two New Species from Northern Madagascar, Candollea 67(2) • December 2012; WCSP (2017). 'World Checklist of Selected Plant Families. 21.01-2017; http://apps.kew.org/wcsp/
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Read more of Cultivation of Aeranthes strangulata Frapp. ex Cordem.
Culture :
Light:
1200-2000 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. Hillerman & Holst (1986) reported success with light levels of 1500-1800 fc. in summer, with levels dropped to 700-1000 fc. in winter.
Temperatures:
Summer days average 78-80F (26-27C), and nights average 60-61F (16C), with a diurnal range of 17-20F (10-11C).
Humidity:
75-80% most of the year, dropping to near 65% for a short time in spring.
Water:
Rainfall is very heavy from late spring to early autumn. Amounts then decrease fairly rapidly at the beginning of the 5-month dry season, which lasts from late autumn to early spring. Cultivated plants should be watered heavily while actively growing. Water should be reduced after new growth is completed in autumn.
Fertilizer:
1/4–1/2 recommended strength, applied weekly when plants are actively growing. Many growers use a balanced fertilizer all year. Others, however, prefer to use a high-nitrogen fertilizer from spring to midsummer and then switch to a high-phosphate formula in late summer and autumn.
Rest period:
Winter days average 68-70F (20-21C), and nights average 48-50F (9-10C), with a diurnal range of 19-22F (11-12C). Rainfall in the habitat is low in winter, but additional moisture usually is available from heavy dew and mist. Cultivated plants need less water in winter, but they should not dry out completely or stay dry for long periods. Fairly regular early-morning mistings between infrequently light waterings should provide sufficient moisture in most growing areas. Hillerman and Holst (1986) report misting their plants about 5 times per week. Fertilizer should be reduced or eliminated until new growth starts and heavier watering is resumed in spring.
Growing media:
Plants may be grown in shallow, well-drained containers or mounted on tree-fern slabs. 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 pot or 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 & Holst (1986) reported that plants have been potted in pure sphagnum moss, perlite, Husky Fiber (Coconut fiber), or fir bark and have grown about equally well in each. Shredded tree-fern fiber may also be used, and varying amounts of chunky perlite and/or chopped sphagnum moss may be added to the potting mix 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. Plants should be repotted immediately if the medium starts to break down or whenever the plant outgrows its container. 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 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

 

 

 

 

 

 

Read more of Cultivation of Aeranthes orthopoda Toill.-Gen., Ursch & Bosser,
Culture:
Light:
500-1400 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. Hillerman & Holst (1986) reported that orchids grown side by side with Aeranges orthopoda grew in light ranging from 400-500 fc. in winter to 1000-1400 fc. in summer.
Temperatures:
Summer days average 78-80F (26-27C), and nights average 60-61F (16C), with a diurnal range of 17-20F (10-11C).
Humidity:
75-80% most of the year, dropping to near 65% for a short time in spring.
Water:
Rainfall is very heavy from late spring to early autumn. Amounts then decrease fairly rapidly at the beginning of the 5-month dry season, which lasts from late autumn to early spring. Cultivated plants should be watered heavily while actively growing. Water should be reduced after new growth is completed in autumn.
Fertilizer:
1/4-1/2 recommended strength, applied weekly when plants are actively growing. Many growers use a balanced fertilizer all year. Others, however, prefer to use a high-nitrogen fertilizer from spring to midsummer and then switch to a high-phosphate formula in late summer and autumn.
Rest period:
Winter days average 68- 70F (20- -21C), and nights average 48-50F (9-10C), with a diurnal range of 19-22F (11- -12C). Rainfall in the habitat is low in winter, but additional moisture usually is available from heavy dew and mist. Cultivated plants need less water in winter, but they should not dry out completely or stay dry for long periods. Fairly regular early-morning mistings between infrequently light waterings should provide sufficient moisture in most growing areas. Fertilizer should be reduced or eliminated until new growth starts and heavier watering is resumed in spring.
Growing media:
Plants may be grown in shallow, well-drained containers or mounted on tree-fern slabs. 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 pot or 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 & Holst (1986) reported that plants grown side by side with Aeranthes orthopoda have been successfully grown when potted in fine fir bark mixes but were potted in a containers no larger than 5 in. (12 cm). Mixes using shredded tree-fern fiber may also be used, and varying amounts of chunky perlite and/or chopped sphagnum moss may be added to the potting mix 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. Plants should be repotted immediately if the medium starts to break down as Aeranges species are prone to rot if conditions around the roots become stale. 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 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

 

 

 

 

 

 

Read more of Cultivation of Aeranthes ramosa Rolfe
Culture:
Light:
500-1400 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. Hillerman & Holst (1986) reported that this orchid grows in light ranging from 400-500 fc. in winter to 1000-1400 fc. in summer.
Temperatures:
Summer days average 78-80F (26-27C), and nights average 60-61F (16C), with a diurnal range of 17-20F (10-11C).
Humidity:
75-80% most of the year, dropping to near 65% for a short time in spring.
Water:
Rainfall is very heavy from late spring to early autumn. Amounts then decrease fairly rapidly at the beginning of the 5-month dry season, which lasts from late autumn to early spring. Cultivated plants should be watered heavily while actively growing. Water should be reduced after new growth is completed in autumn.
Fertilizer:
1/4-1/2 recommended strength, applied weekly when plants are actively growing. Many growers use a balanced fertilizer all year. Others, however, prefer to use a high-nitrogen fertilizer from spring to midsummer and then switch to a high-phosphate formula in late summer and autumn.
Rest period:
Winter days average 68- 70F (20- -21C), and nights average 48-50F (9-10C), with a diurnal range of 19-22F (11- -12C). Rainfall in the habitat is low in winter, but additional moisture usually is available from heavy dew and mist. Cultivated plants need less water in winter, but they should not dry out completely or stay dry for long periods. Fairly regular early-morning mistings between infrequently light waterings should provide sufficient moisture in most growing areas. Hillerman and Holst (1986) report misting their plants about 5 times per week. Fertilizer should be reduced or eliminated until new growth starts and heavier watering is resumed in spring.
Growing media:
Plants may be grown in shallow, well-drained containers or mounted on tree-fern slabs. 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 pot or 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 & Holst (1986) recommended potting in finer fir bark. Shredded tree-fern fiber may also be used, and varying amounts of chunky perlite and/or chopped sphagnum moss may be added to the potting mix 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. Plants should be repotted immediately if the medium starts to break down or whenever the plant outgrows its container. 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 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

 

 

 

 

 

 

Read more of Cultivation of Aeranthes neoperrieri Toill.-Gen., Ursch & Bosser,
Culture:
Light:
1200-2000 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:
Throughout the year, or Summer days average F (C), and nights average F (C), with a diurnal range of F (C).
Humidity:
Near 85% most of the year, dropping to near 80% for 2-3 months in spring.
Water:
Rainfall is very heavy most of the year. Amounts decrease somewhat for a month or so in spring, but the habitat is never truly dry. Cultivated plants should be watered heavily while actively growing, but conditions around the roots should never become stale or soggy.
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:
Growing conditions should be maintained all year, or Winter days average F (C), and nights average F (C), with a diurnal range of F (C). In winter, water should be reduced somewhat for most cultivated plants, especially those grown in the dark, short-day conditions common in temperate latitudes. They should never be allowed to dry out completely, however. If water is reduced, fertilizer should also be reduced.
Growing media:
Plants may be grown in shallow, well-drained containers or mounted on tree-fern slabs. 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 pot or 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 & Holst (1986) reported that plants have been successfully grown when potted in fine fir bark mixes but should be potted in a pot no larger than 5 in. (12 cm). Mixes using shredded tree-fern fiber may also be used, and varying amounts of chunky perlite and/or chopped sphagnum moss may be added to the potting mix 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. Plants should be repotted immediately if the medium starts to break down as Aeranges species are prone to rot if conditions around the roots become stale. 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 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