Seeds Salvia lyrata Purple Knockout. Beautiful dark purple variegated foliage and purple three quarter inch flowers on purple black stems. Grown mainly for foliage of compact rosettes of shiny burgundy leaves that turn purple in the summer and then red in the fall. Pale lilac flowers appear in the spring and summer but are insignificant. Young leaves have a mild minty flavor, used in salads. Growing 18 inches in zones 6 to 9.