Barrett’s Penstemon, Penstemon barrettiae, has woody stems and large glaucous gray leaves with showy lavender flowers in spring. A mature plant in the wild can grow up to 40″ x 70″ but garden plants are generally smaller. Grow in full to part sun in very well-drained, gritty soil with low summer water. Hardy to -10 degrees. Penstemon barrettiae is a protected plant in the state of Oregon and our plants are grown from seed collected in Klickitat County, Washington by Alan Bradshaw of Alplains. His seed lot number 10214.19.