Origin and Habitat: Pachypodium menabeumSN|10825]]SN|10825]] has a very restricted range in central Madagascar, where it grows in the limestone cliffs near Antsalova in the tsingy of Bemaraha. This plateau is on the list of the world-wide patrimony of Humanity and it is the most spectacular place in Madagascar.
Habitat asnd ecology. This species grows on vertical eroded limestone rocks in xerophytic forest together with Euphorbia perrieriSN|33286]]SN|33286]], and tufts of aloes wedged in the cracks of the cliffs.

• Pachypodium menabeum Leandri

Description: Pachypodium menabeumSN|10824]]SN|10825]] is shrub or small bottle shaped tree 2-5 m high, the succulent trunk (caudex) produces candelabra-like branches that feature a very handsome spiralling spination and few leaves in the upper part. This pachypodium has been confused with Pachypodium lamereiSN|10825]]SN|10823]] for a long time because they are very similar, and is often considered a synonym of Pachypodium lamereiSN|10823]]SN|10823]] var. ramosum. It is a very decorative species and can bloom at and early age.
Derivation of specific name. The specific name comes from the homeland of the plant (former Province of Ménabé).
Stem. Base (bole) succulent and spiny shaped like “the bottle gourd” (Lagenaria siceraria), 30-40 thick, with up to 1-2 m long branches.
Leaves: Few, persistent, tufted in the uppermost part of the branches, elliptic to obovate, shortly mucronate, petioles up to 2 cm long and 1-2 mm thick, central rib above depresses below prominent, main nerves parallel about 2 mm apart, secondary nerves net like, ending abruptly toward the margin. Upper face of the lamina (blade) green lower face clear both smooth. Margins slightly wavy and rolled.
Flowers: White up to 5 cm long in 5-10 cm long cymes (an inflorescence in which the first flower is the terminal bud of the main stem and subsequent flowers develop as terminal buds of lateral stems). Corolla tube very short (c. 3 mm long.) and narrowed at the base. Anthers deeply included. Style hairless.
Similar species. Pachypodium menabeumSN|10823]]SN|10825]] belongs to the group of white-flowered pachypodiums. It looks like the more southern short-peduncled Pachypodium lamerei, but is smaller and fatter, has entirely hairless style and the leaves are glabrous (smooth) on both sides. It differs from Pachypodium ramosumSN|10825]]SN|10824]] by its leaves briefly mucronate, non-acuminate and the ultimate innervation not cross-linked.

Bibliography: Major references and fuerther lectures
1) Leandri “Bulletin de la Société botanique de France”, Volume 81, p 141, La Société, 1934
2) Lüthy, J. M. 2004 b. "Die Wiederentdeckung von Pachypodium menabeum (Apocynaceae)". Kakt Sukk 55:10274–280.
3) "Collins English Dictionary" – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

Cultivation and Propagation: Pachypodium menabeumSN|10825]]SN|10825]] is fairly easy to grow both indoors, as well as outdoors in warm climates. In the winters it is partially deciduous, except in very tropical areas.
Growth rate: It is a fairly slow growing plant, but in 10 years it can easily outgrow its indoor location, requiring a 'pruning'. Though branching is usually a response to naturaly injury, or something that happens in older specimens, one can stimulate branching by cutting off its top. It has amazing regenerative properties.
Soil: It needs a draining cactus potting mix.
Repoting: Repot the plant every 3 years; this is quite tricky given all the spines. The best way is to wrap several layers of newspaper around the trunk where it is to be handled.
Waterings: It needs regular water when the plant has leaves, contrary to popular belief, it likes a lot of water in the warm summers, as long as it's planted in a very well draining soil. Indoors it is best to err on the dry side, or it is prone to rot.
Exposures: It like full sun to light shade with warm temperatures.
Propagation: Seeds or division.Fresh seeds results in a remarkable yield of new plants, perhaps 90%, Soak seeds in warm water for 24 hours before sowing in moist sand. Seed start sprouting in just 3-4 days ( but continue to germinate erratically for about 6 month).