Frosty Blue is a whale's tongue agave, named for broad, cupped leaves in a chalky blue-gray that form a bold, symmetrical rosette. It grows slowly and reads as living sculpture, equally at home in a modern pot or a gravel bed.

Give it full sun and gritty, fast-draining soil, and water sparingly, letting it dry completely between drinks. This species is notably cold-hardy for an agave, so a container can stay on a sunny porch most of the year here; just keep winter wet off the crown. Mind the leaf tips when you walk past.