[5] The species is named after the Scottish physician Isaac Lawson, a good friend of Linnaeus.

They are glabrous, sub-sessile, elliptical, and lanceolate (long and wider in the middle; average dimensions are 1.5–5.0 cm x 0.5–2 cm or .6–2 in x 0.2–0.8 in), acuminate (tapering to a long point), and have depressed veins on the dorsal surface.

Its petals are ovate, with white or red stamens found in pairs on the rim of the calyx tube.

[8] During the onset of precipitation intervals, the plant grows rapidly, putting out new shoots.

The leaves gradually yellow and fall during prolonged dry or cool intervals.