As summer wears on, often the only thing in bloom in the garden are hot-weather bedding plants like marigolds and petunias. Here's what to add if you want a little more variety in the peak of summer:
Bee balm (Monarda didyma). Clusters of fuzzy flowers — in red, pink, white or lavender — appear at the top of two-to four-foot plants during summer months. Give the plant moist, well-drained soil in a mostly sunny site (although it will accept light shade). Deadhead to extend bloom.
Nasturtium (Tropaeolum majus). Bright red, orange or yellow flowers bloom from midsummer to frost. Elongating stems are great for containers and, if given great conditions, will even creep across grass. Try a type with variegated foliage — that way you'll double the interest.
Black-eyed Susan (Rudbeckia sp.). If you include several varieties of Black-eyed Susans in your garden, you can have these bright golden blooms all summer. They couldn't be easier to grow — they don't seem to mind less-than-great soils, and they're drought tolerant. R. fulgida (about 2-1/2 feet tall) and R. lanciniata (3 to 6 feet or more) are perennials that spread via rhizomes. R. hirta, an annual that reseeds or a short-lived perennial, blooms in June; it's the shortest at 1 to 2 feet. The perennial forms usually start blooming by midsummer.
Gaura (Gaura lindheimeri). In the tough, unforgiving clay soil and full sun of the editor's garden shines 'Whirling Butterflies'. This three- to four-foot perennial has an airy look because of its gradually elongating wiry stems that bear white butterfly-like flowers, sometimes with tinges of pink. ('Siskiyou Pink' is bright pink.) But the plant isn't as delicate as it looks. It's deeply rooted, grows in a variety of different soils (including alkaline) and is tolerant of drought. In many gardens, it seems to outcompete nearby weeds without becoming a nuisance itself. After a few years, dividing can get you more wonderful gauras. Hardy to USDA Zone 5.
Purple coneflower (Echinacea purpurea). Pinkish droopy petals surround dome-like centers. The five-foot foliage is fairly nondescript, so tuck this perennial behind lower growing plants. Tolerant of relatively poor soils. If you'd like, divide in spring or fall. Hardy in USDA Zones 3 to 8.
Crocosmia. Once a mainstay of Victorian gardens, crocosmia (also, montbretia) offers a dramatic, tropical look. Flowers in fiery hues form along the ends of three-foot-tall arching stems above upright, sword-shaped leaves. Red, red-orange, tangerine, golds, soft buttery yellows are among the options. Crocosmia spreads where winters are warm; in some very warm climates, it may be invasive. Grown from corms. Reliably hardy to USDA Zone 6.