Penstemon is a great native prairie perennial that has colorful tubular flowers on tall spikes loved by butterflies and hummingbirds. Plants grow 1-3' tall depending on variety and have flower colors that include pink, blue, red, purple and white. Penstemon, also known as 'Beardtongue' grows best in full sun in well-drained soil. It is a low-maintenance plant that can tolerate dry soil, thrives in hot, sunny locations and is good for cut flowers. Make sure to give Penstemon room, as they do not like to be crowded out by other plants.