Perennial herb, 60-100 cm high,with soft thick-stems, succulent, hairy, aromatic.  Leaves blades, 2.5-4.5 x 2.5-4 cm, thick and soft, broadly ovate, truncate-subcordate at the base, apex obtuse to rounded, margins crenate, both surfaces densely pubescent with glands; inflorescence a raceme 10-30 cm long; flowers bilabiate, corolla 7-9 mm long, lilac to whitish.

Annual or perennial acaulescent herb with a taproot producing numerous fibrous lateral roots. Leaves, glabrous, forming a basal rosette, petioles 2-15 cm long, blades ovate to elliptic, 2.5-25 x 3-12 cm, base abruptly narrow, apex obtuse, margins coarsely dentate; inflorescence a spike spike, linear-cylindrical, 5-25 cm x 6-8 mm, scape 10-30 cm. long; flowers perfect, corolla lobes 0.5-1 mm long, numerous, sessile, green; fruit a capsule ovate-elliptic 3-4 mm long, seeds brown, oblong 1 x 0.7 mm.

Soft-wooded aromatic shrub or tree 1-6m high.  Leaves ovate or ovate-elliptical, 20-40 x 12-25 cm, acute to short acuminate at the apex, deeply and unequally cordate-auriculate at base, margins densely white-ciliate, petiole winged to the apex; inflorescence a spike, whitish to light yellow, pendulous, 10-20 cm x 3-5 mm; fruit, small, three-angled.

Evergreen tree up to 15 m high with smooth, whitish, variegated and flaking bark, hard and heavy wood.  Leaves simple, entire, opposite in pairs, dark green, leathery, oblong to elliptic, obtuse at the tip, rounded at the base, 15-20 x 5-7 cm, prominent  venation, highly aromatic when crushed; inflorescence a compound panicle 5-10 cm long, flowers numerous 3-4 mm long, white; fruit a subglobose to ellipsoid berry, 8-10 mm long, thickly covered with small convex glands, black when ripe.

Tree, up to 20 m high, very aromatic.  Leaves elliptic-oblong to oblong, 6-12 cm long, obtuse at the apex, round to acute at the base, coriaceous.  Inflorescences cymose; flowers thrice or twice trichotomous, in clusters of up to 9 flowers. Berries globose, glabrous, glandulose.