Hardy and reliable, Agastache 'Black Adder' (Giant Hyssop) is a charming herbaceous perennial boasting bottle-brush, terminal spikes, 6-8 in. long (15-20 cm), packed with fragrant, tubular, two-lipped red-violet flowers emerging from dark buds. Blooming from mid-summer to fall, they provide a remarkably long floral display and add color as well as a lovely spiky texture to the garden.

If you are looking for abundant blooms in shades of magenta for weeks of summer color, Achillea millefolium 'Cerise Queen' is what you need. This eye-catching Yarrow features masses of long-lasting clusters of bright cherry-pink flowers with white centers. They rise elegantly atop a pleasantly aromatic, semi-evergreen, mid-green fern-like foliage that nicely compliments the cheerful flat umbel flowers.

Award-winning Nepeta racemosa 'Walker's Low' (Catmint) is a popular herbaceous perennial noted for its massive lavender-blue blooms on short spikes, atop aromatic, gray-green foliage in early summer, continuing on and off through early fall if spent flowers are regularly removed.

A breathtaking beauty, Eremurus x isabellinus 'Cleopatra' (Foxtail Lily) is a tall perennial boasting glowing tangerine flower clusters rising high on imposing stalks, adding drama and spectacular vertical lines in the garden. Soaring from a rosette of strap-shaped green leaves from early to mid-summer, each graceful flower spike is richly covered with hundreds of tiny apricot blossoms which open from the bottom upwards for a long-lasting display. Since the foliage withers back during the flowering period, plant your Eremurus among ground covers, late-flowering perennials, or tall grasses that will hide the short-lived foliage and provide added attractiveness.