I usually associate Euphorbias with Africa or the Mediterranean region but this one is from South east Asia and India. It is found in Indonesia, Malaysia,Thailand and Burma where it is given the common name of Indian Spurge tree or in Indonesian Sudu-Sudu. In the garden it forms a large rounded shrub with unusual obtuse five angled branches tipped with small spines. I guess you could give it that 'architectural' plant tag as it is quite stiff and almost plastic like in appearance. I have a few specimens which I am growing in 25cm pots and I think they would look good on a roof or balcony garden where they would certainly withstand possibly windy or hot and dry conditions. The only problem I have encountered in growing it is with scale insects which often hide underneath the tough waxy leaves, remaining fairly invisible until you notice that ants are starting to run up the stems in search of honeydew exuded by the scale. This Euphorbia will grow in sun or shade and requires minimal water or attention. It is reasonably cold hardy but will defoliate if frost occurs.