FLORA OF VIETNAM Lamiaceae Plectranthus amboinicus (Lour.) Spreng.
N. Vietnam, Thai Nguyen prov., Vo Nhai distr., Than Sa municipality, vicinities of Kim Son village (N 21°48′ E 105°54′), 23.3 km to 18° of Thai Nguyen city. Primary dry broadleaved evergreen forest on very steep rocky slopes of remnant karst limestone ridge at elev. about 300 m a.s.l. Lithophytic forb up to 1 m hg on open rocks. Flowers blue-violet. Very common, especially on open rocks on tops of ridge after fire.