Montrose White is a calamint that blooms like an annual on a perennial's schedule: clouds of small white flowers from early summer to frost over minty-fragrant foliage, with no deadheading required. Because it's sterile it never seeds around; it just keeps flowering while bees work it from morning to dusk.

Give it full sun and well-drained soil. It handles drought, dry rocky ground, and deer pressure once established. At 1 to 2 feet it makes an airy filler along paths and between bolder perennials.