3 to 6 ft.
1 to 2 ft.
USDA zones 5-9
Arctic ice mullein is a striking flowering plant. Since it is a biennial, it lives only for two years. The first growing season, the large, woolly silver leaves form a basal rosette. The following growing season, a sturdy stem rises from the center and holds one or more flower stalks bearing round, yellow flowers. After flowering, the plant dies. Seedlings may grow and replace the original plant if the seed is allowed to mature and disperse.
Arctic summer mullein has been a successful cultivar at the Xeriscape Demonstration Garden. Its fuzzy leaves and clear yellow flowers make it an attractive plant. It reseeds readily, so it is necessary to thin the seedlings so it doesn't overtake an area.
Thin seedlings as needed. After flowering, remove the plant when it dies.