Pachypodium geayi is an extraordinarily decorative bottle-shaped tree, 4-7(-8) m high whit stem and branches metallic grey thick and succulent. It strongly resemble cereiform cacti, with highly succulent, cylindrical stems armed with sharp spines. P. geayi is often confused with the more common Pachypodium lamerei, but easily distinguished by having thinner leaves accented with a prominent midrib of a different colour than the rest of the leaf and in the hairs which adorn the young branches and the leaves. P. geayi is one of the largest of the Madagascar species and may be regarded as more decorative than Pachypodium lamerei.

Origin and Habitat: Southwest Madagascar.

Cultivation and Propagation: Pachypodium geayi is fairly easy to grow both indoors, as well as outdoors in warm climates and can grow at about 10 cm a year. In the winters it is deciduous, except in very tropical areas. It is a magnificent form/accent plant. It growing requirements are very similar to those of Pachypodium lamerii, but lameri is the slightly faster grower and more gardening friendly.
Growth rate: It is a fairly slow growing plant which in 10 years it can easily outgrow its indoor location, requiring a 'pruning'. Though branching is usually a response to natural 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.
Warning: The body of this plant is very spiny and dangerous to handle.
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). They are also propagated by removal of truncheons. Carefully cut off the offshoots, they should be allowed to dry for 5 to 8 days before potting up.