Houphan Prov., Viengxay Distr., Khang Pa Pong village, around point 20°19′41.4′'N 104°25′10.6′'E.
Primary and secondary broad-leaved evergreen dry forest on very steep rocky slopes of highly eroded mountains composed by solid marble-like limestone at elev. 1000-1100 m a.s.l.
Shrub 1-2 m tall on rather open rocky slope and on mountain top. Flower buds whitish. Very common.