Verbena bonariensis L.
purple-top
Perennial; stems hairy or scabrid, erect, ± square, to c. 3 m tall. Lvs sessile, 3-17 × 1-6 cm, oblong-lanceolate to ovate, coarsely and irregularly toothed, strigose with bulbous-based hairs denser above than below; veins strongly impressed above; base usually amplexicaul, sometimes subcordate or cordate; apex acute. Infl. much-branched, densely hairy, composed of spikes; spikes closely packed, 0.8-3 cm long at maximum flowering, not elongating much at fruiting, rather stout; fls dense. Bracts ± = or slightly > calyx, lanceolate, hairy, keeled. Calyx c. 3 mm long, hairy, purple, ± glandular-scaly; teeth acuminate or acute, similar to bracts. Corolla tube nearly 2× length of calyx, hairy outside; limb 2-3 mm diam., mauve or purplish, often drying deep blue. Nutlets 1-1.5 mm long, oblong, brown on dorsal surface, longitudinally ribbed, white-papillate on flattened ventral surface.
N.: common to abundant N. of the Volcanic Plateau, and on the E. Coast, generally uncommon further W. and S.; S.: common in lowland areas of Nelson and Marlborough, rare and very local further S. to Otago; K.: Raoul Id.
Eastern S. America 1871
Roadsides, waste places in and around settlements, open and modified habitats.
Purple-top is presumably an escape from cultivation although it is rarely grown now. Occasional plants in different parts of both main islands correspond to var. conglomerata Briq. rather than var. bonariensis but others seem intermediate. Plants corresponding to var. conglomerata differ in that the spikes are so densely packed that they give an almost corymbose appearance to the infl., and the corolla tube is 2-3×, rather than c. 2×, the length of the calyx.
