– Pachypodium rosulatum (2013)
By Rita Taylor (April 2013)
This spiny wonder is a succulent dwarf shrub from Madagascar, where it is one of the most widespread species and can be found almost everywhere on the island. In the wild, this pachypodium grows in full sun in rock crevices or in pockets of humus.
Of interest, too, is that the wild-collected plants have smooth exteriors, but the cultivated plants tend to be covered in spines, as is mine.The mature plant is irregularly lobed with short, tapered branches that divide near the tips to form a coral-like crown.
Rosulatum means rosetted and refers to the tufts of thin, smooth, dark-green leaves. Gracilis is Latin for slender and might also refer to the leaves. This plant does well in full sun, but apparently can also tolerate some partial light shade. It does need well-drained soil and can be watered regularly, but be careful not to overwater.
P. rosulatum is similar in its growth form to P. densifloruman and P. horobense. They all grow a squat base with many short branches, but P. rosulatum has the shortest branches.
The differences among these three species are in their mature size, spine density and flower petal shape. All three have lovely yellow flowers; however, the P. rosulatum flowers are on shorter stalks, are a brighter yellow and do not have center cones. I think it very interesting that one unnamed source stated, “Flowering terminates the longitudinal growth, causing the plant to branch after each flowering event.”
I aspire to be a good plant parent and keep this specimen in great shape and ready for the 2014 show. Although I have always liked caudiciform plants, this is my first pachypodium. I do hope it doesn’t mind being in the company of all my Adenium obesum plants.