Perovskia
Irresistible to pollinators and gardeners alike, Perovskia ranks as one of the great garden plants of all time. These semiwoody perennials carry clouds of small blue flowers on stems that grow 2–4' tall, depending on the variety. The effect is a charming, feathery haze of soft blue against silvery gray, aromatic foliage. An exceptionally long bloomer, Russian Sage is also vigorous and hardy, ignoring heat, drought, and pests while always looking fresh. The varieties listed here make superb companions for Phlox, Rudbeckia, Sedum, and Ornamental Grasses.