Collinsonia canadensis L.

Erect, branched above, to 12 dm; lvs several pairs, ovate or ovate-oblong, acuminate, glabrous, the lower 1–2 dm, on petioles to 1 cm, the upper progressively smaller and the uppermost commonly sessile; panicles 1–3 dm, divergently branched, often compound with branches from the uppermost lf-axils; fls all paired at the minutely bracteate nodes of the infl; cal 2.5–4 mm at anthesis, weakly bilabiate, 8 mm in fr; cor 12–15 mm, the lower lobe oblong, nearly as long as the tube; stamens 2; 2n=50. Rich woods; Que. to Mich. and s. Wis., s. to Fla. and Ark. July–Sept.

It is a temperate plant. It is best in rich, well-drained soils. It needs a protected partly shaded position. It is resistant to frost but damaged by drought. It suits plant hardiness zone 3-9.

Caution: The leaves can cause vomiting.

Plants are grown from seeds.