Adenium socotranum Vierh.
Adenium socotranum is endemic to the island of Socotra. It is by far the largest species, reaching a height of 15 feet (4.6 m) with a cylindrical trunk up to 8 feet (2.5 m) in diameter at the base. It has a very short growing season. Plants rarely leaf out before mid summer, and stem growth occurs in a single spurt that lasts for only a few weeks. The pink flowers appear in spring while the plants are leafless. The species is easy to grow, but it is very slow. It's difficult to flower. Desert heat and cool nights both seem to inhibit flowering. Under warm greenhouse conditions flowering seems to be triggered by an irrigation during the spring dry season.
The Above Two: A flat of 2-year old Adenium socotranum seedlings. Right: The seedlings bare-rooted for planting out. This species has huge variation in seedling vigor, more than any other adenium that I've grown.
Adenium socotranum seedlings at six years of age. The ruler is 12 inches/30 cm.
Above 3 images: Left: Adenium socotranum flowering for the first time at 10 years age. The plant was beheaded when 7 years old to make it branch. Center: The same plant at 20 years from seed. Right: Its caudex at 23 years old in a 24-inch box. This is the most vigorous soco that I've grown out of about 30.
Adenium socotranum in the Wild
Few of us mortal humans will live long enough to grow Adenium socotranum to its full potential size. The next best option is to enjoy photos from travelers who have been fortunate to visit Socotra. Enjoy this eye candy, with gratitude to several photographers!
Adenium socotranum seedling near Qaysoh. Photo: Dylan Hannon
A dark-flowered Adenium socotranum seedling at Wadi Darhu. Photo: Dylan Hannon
Adenium socotranum on Homhil Plateau. Photo: Dylan Hannon
Adenium socotranum. Photo: John Lavranos.
Above Two Images: Flowers of Adenium socotranum. Photos: Greg Corman