452. KALANCHOE ERIOPHYLLA Crassulaceae. E.J. Lucas

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1 452. KALANCHOE ERIOPHYLLA Crassulaceae E.J. Lucas Summary. The Madagascan Kalanchoe eriophylla Hilsenb. & Bojer ex Tul. (Crassulaceae), is illustrated. A full description is provided, and its taxonomy, natural distribution and cultivation are discussed. Kalanchoe, a member of the Crassulaceae, is a genus of free standing, sturdy shrubs, sub-shrubs or occasionally herbs, seldom scramblers or climbers. The genus differs from Bryophyllum in that Kalanchoe species bear erect flowers (pendent in Bryophyllum), and young plants are not usually produced from the leaf margin as they frequently are in Bryophyllum (for a more detailed discussion about the distinguishing characteristics, see the account of B. gastonisbonnieri (Plate 451) in this issue; also Lauzac-Marchal, 1974; Boiteau & Allorge-Boiteau, 1995). Like Bryophyllum, the centre of Kalanchoe diversity is in Madagascar; however Kalanchoe differs in that it has a more widespread distribution than the endemic Bryophyllum. In terms of species, Kalanchoe sensu stricto is by far the most numerous genus of Crassulaceae on Madagascar. The genus comprises approximately species, c. 60 of which are from Madagascar (Boiteau & Allorge-Boiteau, 1995). Species of Kalanchoe are represented in almost all of the many habitats found on the large, mountainous and climatically variable island of Madagascar and are missing only from the large central plateaux where much of the ancient vegetation has been lost to burning (Boiteau & Allorge-Boiteau, 1995). Although slow growing, the rather diminutive Kalanchoe eriophylla is especially attractive for cultivation on account of its unusual woolly leaves and pink flowers. It is also unusual among species of Kalanchoe in its adaptation to a montane habitat, exhibited by its creeping, rooting main stem. As with most species of Kalanchoe and Bryophyllum, the ease with which this species can be propagated contributes to its suitability for cultivation as a house-plant. It can also be used as a ground cover species in mixed plantings of cacti and succulents. Kalanchoe eriophylla was initially described in 1857 by R. Hilsenbeck and W. Bojer in the contributions to the Flora of 232 # Royal Botanic Gardens, Kew Published by Blackwell Publishing Ltd, 108 Cowley Road, Oxford, OX4 1JF, UK and 350 Main Street, Malden, MA 02148, USA

2 Plate 452 Kalanchoe eriophylla CHRISTABEL KING

3 Madagascar compiled by Louis-RenÑe Tulasne. The species epithet chosen by them is a combination of the two Greek words signifying woolly leaves. In this description, the authors record a single collection of the species, collected by Bojer on Mt Antogona, Imerina province. The specimen of K. eriophylla from which our plate was drawn was donated to Kew in 1955 by B. Perkins. Apart from material from this source, this species is represented in the Kew herbarium by three collections, Baron 972 and 1032, both collected in central Madagascar in 1882, and Kitching s.n. collected in the central Madagascan Ankaratra massif in Boiteau & Allorge-Boiteau (1995) cite additional collections from Mt Antogona, west of Tananarive, and in the environs of Tananarive, Imerina Province; they consider the species to be very abundant. One of several Malagasy vernacular names for this species, Felatanantsifoana, translates as palm of the hand never empty, reflecting the value of this species to the indigenous Malagasy people, as a talisman believed to favour the acquisition of riches. Pieces of the plant are sold in markets and worn on the person to bring good luck (Boiteau & Allorge-Boiteau, 1995). Kalanchoe eriophylla is cultivated intermittently in botanic gardens and is available from specialist garden centres and succulent enthusiasts. Despite its frequent occurrence in the wild, it is not a common house-plant, particularly when compared to other species of Kalanchoe such as the closely related Kalanchoe tomentosa Baker (PANDA PLANT or PUSSY EARS) which is widely available and commonly cultivated. Kalanchoe eriophylla differs from K. tomentosa in having a rounder leaf tip without brown or yellow markings. CULTIVATION. The creeping habit and woolly leaves, which make K. eriophylla so appealing, are adaptations to higher altitudes, protecting the plant from desiccation and increased levels of ultraviolet light. A consequence of this is that cultivated individuals require slightly cooler and drier, well-drained conditions and less direct sunlight than lower altitude species. Plants of this species should be grown in small pots in a temperate glasshouse, with a minimum temperature of 4 5 C and a maximum of C. They should be watered sparingly in the summer months and then maintained drier and cooler throughout the winter. A highly porous, freely-draining mixture which has a low humus content (i.e. without the addition of much nitrogenous material) should be used. As much light as possible should be provided in the winter to # Royal Botanic Gardens, Kew

4 encourage growth and shoot formation. Plants should be maintained in light shade throughout the summer months, as excessive light levels may cause discoloration of the foliage and fading of the flowers. Like Bryophyllum, Kalanchoe species are shortday plants which remain vegetative when day lengths are longer than 13 hours. Flowering may be induced by exposing the plants to a regime of less than 11 hours of daylight, applied continuously for 2 9 weeks. When flower buds are visible, the natural daylight pattern can be resumed, but the quality of flowers may improve if the shorter day length regime is sustained. It is important to ensure adequate ventilation at all times. Kalanchoe eriophylla may be propagated by cuttings from vegetative stems. Cuttings 5 to 7 cm long of healthy, leafy stems are made in the early spring; these are inserted to an approximate depth of 2 3 cm in a permeable soil or sandy medium kept slightly moist, but not wet, and out of direct sunlight. Rooting usually occurs within two to three weeks. Kalanchoe eriophylla Hilsenb. & Bojer ex Tul. in Ann. Sci. Nat., Bot. sñer. 4, 8: 149 (1857). Type: Madagascar, Mt Antogona, Imerina, 1887cos, Bojer s.n. 887 (holotype P). DESCRIPTION. Perennial herb to 30 cm. Stems stiff, decumbent or pendulous, 50 mm long, c. 5 mm diameter below the peduncle, covered in brown, peeling bark. Leaves opposite and decussate, sessile, densely crowded into rosettes at the plant base and irregularly clustered above; lamina succulent, sub-ovoid to subcylindrical, mm long, 6 17 mm wide, c. 5 mm thick, covered in long, trifurcate white hairs, the base truncate to amplexicaule, apex obtuse, margins entire or occasionally crenulate. Inflorescence an erect, simple or branched cyme arising from the centre of the terminal leaf rosettes, peduncle 9 15 ( 20) 1:5 2 mm thick at the base, covered in white trifurcate hairs, furnished at the mid point or in the upper portion with one or two pairs of reduced leaves 3 6 1:5 2 mm; cymes each bearing 2 7 flowers, subtended by a pair of tardily caducous, foliar bracteoles mm, slightly curved towards the stem. Flowers erect to semi-erect, entirely covered in trifurcate hairs, pedicels 5 7 mm; sepals 4, partially fused into a tube to 1.5 mm long, bearing 4 free, erect, light green, triangular, acute lobes ( 5) mm; petals 4, partially fused into a tube to 6 mm long, bearing 4 free, reflexed, pale pink to pale purple, sub-obovate to obovate, rounded (sometimes shortly-apiculate) lobes, mm. Stamens 8, free, flattened, biseriate; anthers sub-reniform, c. 0.3 mm long 0.7 mm wide; 4 oppositipetalous stamens inserted mm above base of corolla tube and slightly exerted from it, filaments mm 0.3 mm, 4 epipetalous stamens inserted 234 # Royal Botanic Gardens, Kew 2002.

5 Kalanchoe eriophylla. A, flower, 2; B, calyx, 2; C, corolla exterior, 2; D, stellate hair from corolla exterior, 6; E, one lobe of corolla, internal view, 4; F, stamens, 2 views, 8; G, gynoecium, 8; H, carpel, l.s., 8. Drawn by Christabel King. 1 2 mm above base of corolla tube and entirely enclosed within it, filaments mm mm; all filaments adpressed to the carpels then narrowing abruptly and twisting mm below the anthers, ultimately reflexed away from the gynoecium. Ovary superior, to 3 mm, carpels united slightly above base, each carpel subtended by a single, sub-quadrangular, deeply emarginate nectary scale, mm, styles c.1.5 mm long, apically reflexed. Seeds obovate, apically obtuse, bearing short projections along their length, approximately 40 seeds per carpel (Hamet & Marnier, 1964). DISTRIBUTION. Madagascar, central highlands. HABITAT. High altitude igneous outcrops and rocky places. ACKNOWLEDGMENTS. Thanks go to Daniela Zappi for constant encouragement and to Nigel Taylor for helpful criticism. REFERENCES Boiteau, P. & Allorge-Boiteau, L. (1995). Kalanchoe (CrassulacÑees) de Madagascar: SystÑematique, Ñecophysiologie et phytochimie. Karthala, Paris. # Royal Botanic Gardens, Kew

6 Hamet, R. & Marnier, J. (1964). Le Genre Kalanchoe au Jardin Botanique Les C edres. Archives MusÑeum Nationale d Histoire Naturelle, sñer.7, 8: 35, pl. III. Lauzac-Marchal, M. (1974). RÑehabilitation du genre Bryophyllum Salisb. (CrassulacÑees-KalanchoideÑees). Comptus Rendus Hebdomadaires des SÑeances de l AcadÑemie des Sciences (Paris), sñer. D, 278: # Royal Botanic Gardens, Kew 2002.