When late July arrives, your garden may be ready for its own summer vacation. Many perennials, like peonies and lilies, are at their best in May and June. Annuals that provide months of garden color before going to seed often need cutting back in mid-summer. Turning to flowers that peak in late July will give your garden a welcome pick-me-up before fall stalwarts like chrysanthemums begin to perform.
Bluebeard (Caryopteris x clandonensis) is an aromatic, deciduous shrub hardy to minus 20 degrees Fahrenheit. It has a low, mounding habit and clusters of airy blue flowers that account for its other common name, blue mist. Plants begin blooming in July and continue through September. 'Summer Sorbet' is a bluebeard cultivar standing up to 3 feet high and wide. Its variegated, gold-edged green leaves provide continuing garden interest. Use bluebeard, recommends the Missouri Botanical Garden, as a low hedge or mass in a perennial or shrub border. It requires well-drained soil and full sun and does best in averagely moist, loose loamy soil. Plants in poorly drained locations are susceptible to crown rot.
Tall larkspur (Delphinium exaltatum), a buttercup family perennial, grows wild throughout the eastern United States. Hardy to minus 20 degrees Fahrenheit, it stands between 4 and 6 feet tall and up to 2 feet wide. Its deep green, lobed foliage is more abundant than the majority of other wild larkspur. Blooming from July to September, tall larkspur has upright stems with ascending, clear blue, 1-inch spurred blooms. Plants are susceptible to several diseases, including powdery mildew and crown rot.
Tall larkspur does best where summers are cool. It's most attractive, according to the Missouri Botanical Garden, planted in groups. Use it in a perennial borders or native plant garden with full sun and rich, well-drained averagely moist soil. Provide afternoon shade where summers are hot and protection from heavy winds. Removing spent flowers stems will encourage additional bloom.
Garden Phlox 'Purple Flame'
Perennial garden phlox (Phlox paniculata), hardy to minus 30 F, is a July-to-September bloomer valued for its showy, sweetly fragrant flower clusters. The 'Purple Flame' cultivar stands up to 18 inches high with a 1-foot spread. It has narrow, lance-like, deep green leaves. Dense, tubular flowers appear in a large--up to 6 inches across--conical cluster atop each of its multiple stems. Attractive as cut flowers, they have purple petals around deeper purple centers.
Plant garden phlox in full sun to part shade. It likes fertile, consistently moist soil. Provide adequate air circulation to prevent powdery mildew, advises the Missouri Botanical Garden. Water plants from beneath, and mulch in summer to cool the roots.