Perennial flowers are a gardener’s best friend, returning year after year with little maintenance. But some bloom for on ...

Both varieties produce a moderate amount of purple flower spikes in summer. All lamb’s ears are among the most heat-tolerant of perennials, and they’re hardly ever bothered by deer or rabbits.

But everybody likes lavender (Lavandula). It is one of the few perennial plants in the blue, purple and mauve hues. And ...