300 ROCKY MOUNTAIN (Beardtongue) Penstemon Strictus Flower Seeds BLOOM TIME: Spring HARDINESS ZONE: 3 - 9 PLANT HEIGHT: 12 - 36" . . . PLANT SPACING: 15 - 18" LIGHT REQUIREMENTS: Sun . . . SOIL / WATER: Dry Attracts bees, butterflies, and birds including HUMMINGBIRDS.