The Rocky Mountain Penstemon (Penstemon strictus) is a penstemon with showy blue flowers.This species is a herbaceous perennial with a few stems rising nearly straight up from a thick crown. The leaves are long and narrow, with stem leaves smaller and especially narrower than the basal leaves. The leaves are entire and smooth, or possibly downy near the petiole. The inflorescence is a spike (technically a thyrse of 4 to 10 verticillasters). The corolla is 24 to 32 mm (1 to 1.5 inches) long, deep blue with a violet tube, and smooth.