The border penstemons provide a range of vivid colours, multiple spikes of flowers, normally held well above the simple, narrow-leaved foliage. Species tend to flower May, June, but with hybrids (many with a P. campanulatus parent) extend flowering through summer. There are over well over 250 species from North America and Mexico, many of which do require full sun and a well drained soil to extend their longevity. Leave the foliage of these untouched over winter and then cut down in spring, once new growth has formed. There are some species, eg. P. pinifolius which are hardier and suitable for the rock garden.