Phlox are a mainstay in the summer garden
The summer perennial border is a beautiful thing. Many perennials are at the top of their game - lush foliage and impressive blooms. Even in the gardens of the most adventurous gardeners, you will typically find some of the mainstays - coneflowers, black-eyed Susans, day lilies, and garden phlox.
Garden phlox, botanically known as Phlox paniculata, are a staple in summer gardens. They provide brilliant color beginning in mid to late June and continuing through August or September at heights from 11/2 to 4 feet. Phlox mix well with most other annuals and perennials. Suitable companions include hummingbird mint (Agastache), catmint (Nepeta), beardtongue (Penstemon), Russian sage (Perovskia), Salvia, and Sedum.
Plant phlox in moist, but well-drained, fertile soil. They struggle in periods of drought so be prepared to water them during dry spells. A thin layer of mulch will also keep their roots cool. They prefer full sun, but will perform adequately in light shade.
Remove faded flowers to keep them blooming as long as possible and to keep plants looking their best. After frost, cut them back to within 6 inches of the ground. Put foliage in the garbage, not in the compost pile just in case there are powdery mildew spores lurking on some of the leaves.
Another reason to plant phlox: they are attractive to both hummingbirds and butterflies.
The phlox our mothers and grandmothers grew in their gardens were often plagued with powdery mildew. Many of today's selections have been bred to resist powdery mildew, but it is still a good idea to take some precautions.
Give them good air circulation by planting with ample space between them, and water them at the base of plants. Overhead watering, whether from the hose or the heavens, promotes the incidence of powdery mildew even on resistant varieties.
Here are some of the best mildew-resistant varieties you should consider adding to your landscape.
Cosmopolitan is a dwarf variety rarely reaching 18-inches tall and wide. Flower clusters with hot pink petals surrounding a red eye on deep green foliage make this one a winner.
The large, pure white flower clusters of David light up the summer garden. Sturdy plants with stiff, upright stems rarely need staking even though its heavy blooms sit atop 3- to 4-foot stems.
David's Lavender was found in a group of David seedlings. Similar in size to his dad, it boasts deep lavender pink flowers with a white eye that glow as the sun goes down.
Eva Cullum has rich pink blooms with a pinkish-red eye. It grows 2- to 3-feet tall.
Bright lavender eyes surrounded by cool lilac petals distinguish Franz Schubert. It also reaches to 3-feet tall.
Lord Clayton sports unique cherry-red flowers from late June to September. It stays more compact growing just 30-inches tall and wide.
The pale blue flowers of Katherine are the perfect choice for a border filled with soft, pastel blooms. The Chicago Botanic Garden calls Katherine one of the very best mildew resistant varieties.
The Pixie series gives us Pixie Miracle Grace and Pixie Twinkle. I have just recently added Pixie Miracle Grace to my garden. I love its bright, white-eyed, lavender-purple flowers. Pixie Twinkle has baby pink blooms with dark pink centers. They both have dark green, leathery foliage; stay more compact - about 18-inches tall; and bloom abundantly from mid summer into fall.
I don't use much red in my landscape, but if I did I'd choose Red Riding Hood. The large intense red flowers sit atop short 15-inch stems.
The biggest problem you'll have with phlox is choosing which varieties to plant in your garden. Just a few plants make a dramatic impact in the border. Be sure to plant some near your deck or patio where you will enjoy their subtle, but sweet fragrance. It's strongest in the evening. Cut some and enjoy the fragrance inside, too.
•Diana Stoll is a horticulturist and the retail manager at The Planter's Palette, 28W571 Roosevelt Road, Winfield. Call (630) 293-1040 or visit planterspalette.com.