genus Penstemon - large genus of subshrubs or herbs having showy blue or purple or red or yellow or white flowers; mostly western North Americaasterid dicot genus - genus of more or less advanced dicotyledonous herbs and some trees and shrubs cliff penstemon, Penstemon rupicola, rock penstemon - one of the West's most beautiful wildflowers; large brilliant pink or rose flowers in many racemes above thick mats of stems and leaves; ledges and cliffs from Washington to California Penstemon whippleanus, Whipple's penstemon - wine-lavender to black-purple flowers in several clusters on the upper half of leafy stems; Montana south through the Rocky Mountains to Arizona and New Mexico |