Species Information About the Phlox Genus

Description

• Named for the Greek word “phlox,” meaning “flame,” the Phlox genus is noted for its array of brightly colored flowering plants. Flowers may be white or various shades of blue, purple or pink, depending on the species. Some cultivars have bicolored flowers. Phlox vary in size from low, spreading ground covers less than 6 inches high to large, shrublike species more than 5 feet tall. Although they vary in color and size, most phlox flowers consist of a funnel-shaped corolla with five, fused petals and five stamens.

Tall Varieties

• Native to Ontario, Canada to Georgia, garden or summer phlox (Phlox paniculata) is a dependable perennial in U.S. Department of Agriculture plant hardiness zones 4 through 8. Often found growing along sunny wooded borders and moist stream banks, garden phlox typically grows about 4 to 5 feet tall and 2 feet wide.

  Meadow phlox (Phlox maculata) grows about 3 feet tall and is hardy in USDA zones 3 through 8. Meadow phlox grows well in full sun to part shade and prefers moist, organic soil. Both types of phlox bear clusters of fragrant, colorful blooms throughout summer into early fall and make good cut flowers.

Ground Covers

• Hardy in USDA zones 3b through 10, moss phlox or creeping phlox (Phlox subulata) is a low-growing, spreading variety, often used for ground covers and in containers and rock gardens. Moss phlox grows about 6 to 12 inches tall and blooms from spring to early summer. Flower colors include red, white, pink and lavender.

  Also called creeping phlox, Phlox stolonifera forms dense, spreading mats and is hardy in USDA zones 5 through 9. It tolerates full sun to part shade and does well in moist, wooded areas. Creeping phlox blooms throughout summer and grows up to 12 inches tall.

Diseases and Pests

• All Phlox species are susceptible to powdery mildew (Erysiphe cichoracearum), a grayish-white fungus that occurs on leaves in warm, humid conditions. When purchasing phlox, look for cultivars that are disease-resistant, such as Phlox paniculata “David” or Phlox maculata “Alpha.”

  Two-spotted spider mite (Tetranychus urticae) is a troublesome pest that covers foliage with fine webs and causes leaves and stems to turn yellowish-green. To control spider mites, spray plants with 2 tablespoons of cooking oil and 2 tablespoons of baby shampoo mixed with a gallon of water. If you add 2 tablespoons of baking soda to this formula and shake well, you then create a fungicide for powdery mildew. Spray plants every five to seven days, but do not spray in direct sunlight to avoid damaging the plant.