Perennial to over 1 m tall with purplish stems. Leaves mostly 10-15 cm long, entire or toothed, oblong to narrowly lanceolate. Flower clusters branched, sticky-hairy; summer. Flowers 2.5-3 cm long, suddenly swelling near the centre, white or pale violet, generally with lined nectar guides. Sterile stamen hairy.

W USA

Leaf margins saw-toothed, corolla not bearded within, flowers white to pink.

 

Other cultivated species include:

P. campanulatus Willd. with long-pointed linear to linear-lanceolate leaves and reddish purple to violet flowers;

P. newberryi A. Gray, Mountain Pride, from SW USA, a mat-forming plant to about 25 cm tall with leaves to about 3 cm long and deep pink to red flowers with woolly anthers;

P. hirsutus Willd from E N America, which flowers in late summer, has purple flowers with white lobes and is sometimes grown as the cultivar, P. 'Pygmaeus', a low plant with abundant flowers;

P. serrulatus Menz., Cascade Penstemon, from NW America, with leaves entire to toothed or cut, and blue to dark purple flowers.

Source: Spencer, R. (2002). Scrophulariaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.