Phlox are versatile plants within the garden. Creeping phlox make an excellent groundcover when used in borders or rock gardens, and tall garden phlox are attractive when placed at the back of a perennial garden bed. They are a low-maintenance plant that multiplies quickly, and they have a lovely fragrance. Phlox are a perfect perennial for any garden, attracting hummingbirds and butterflies.
Types of Phlox
Garden phlox, or Phlox paniculata, grows in clumps and produces beautiful clusters of blooms in the summer season. They reach a height of 2 to 4 feet. Similar to garden phlox is the spotted phlox or Phlox maculata; it flowers earlier than garden phlox, with flower heads that are conical in shape. Spotted phlox grows to a height of 2 to 3 feet. Another variety of phlox is the woodland phlox (Phlox divaricata). Woodland phlox blossoms in the months of April through June, with flower clusters that are blue/violet in color. It reaches a height of 12 to 15 inches. Then there are the low-growing, carpetlike phlox, often called creeping phlox or moss phlox. It grows low to the ground (4 to 6 inches in height), forming a dense mat of flowers.
Phlox Blossom Colors
Garden phlox come in a variety of flower colors: white, pink, red, blue and purple. According to Iowa State University, there are several cultivars of spotted phlox available: 'Alpha', rose/pink blossoms with darker eyes; 'Omega', white blossoms with pink eyes; 'Miss Lingard', white blossoms, and 'Rosalinde', purple/pink blossoms. Varieties of woodland phlox include 'Fuller's White', white blossoms and 'Chattanhoochee', lavender/blue flowers that have purple centers. Creeping phlox colors include white, pink, red, blue and purple. Iowa State University recommends planting varieties such as 'Emerald Blue', 'Emerald Pink', 'Scarlet Flame' (rose-pink) and 'White Delight'.
Both garden phlox and spotted phlox are good for the back of perennial garden beds; growing from 2 to 4 feet tall, they make an excellent backdrop for shorter growing perennials. Woodland phlox are seen in shady woodland gardens as well as perennial beds that are in shady spots in the garden. Creeping phlox are used as a border plants and groundcover; they can also be found growing in rock gardens.
Powdery Mildew and Garden Phlox
Garden phlox are susceptible to powdery mildew. Plants that are infected with powdery mildew will have a grayish/white powderlike substance on their leaves and stems. Eventually, the leaves yellow and die. To alleviate this problem, space the plants far enough apart so that the air can circulate among them. You should also water in the early morning hours so the plants have time to dry out during the day. To avoid the problem of powdery mildew entirely, select a mildew-resistant variety such as 'David' or 'Eva Cullum'.
The Butterfly Garden
A butterfly garden would not be complete without phlox, as they are one of the favorite nectar plants of butterflies and hummingbirds. Butterfly gardens should be set in a sunny location, as butterflies need the sun to warm their body temperature. Rocks should also be placed among the garden, as rocks retain the sun's heat. Butterflies will sit on the rocks on a cloudy day to absorb the heat from the rocks. According to Iowa State University's Reiman Gardens, phlox are one of the nectar plants that are required by the Eastern Black Swallowtail and the Tiger Swallowtail--two beautiful species of butterflies.