Story and Photos by Yvonne Lelong Bordelon

Woodland phlox, also known as wild sweet William, is a low-growing native perennial sporting masses of white, pink, blue, and lavender blooms. Pollinators, such as swallowtail, gray hairstreak, and western pygmy butterflies, are attracted to the fragrant flowers. Phlox forms colonies, spreading by shallow roots from stem nodes, making it a good, colorful ground cover for part-shade areas.

The semi-evergreen compact cultivar ‘Blue Moon’ makes a great ground cover. Clip the plants after they bloom in spring to encourage more dense growth. Fox tail fern (Asparagus), Lycoris, and daylilies are good companions in Tricia Day’s Baton Rouge garden.

Most varieties go dormant after blooming, so in shade gardens or beds it is good to plant phlox in small groups among summer-blooming perennials and annuals that can fill in the empty spots. Good companion plants include spring bulbs such as daffodils (Narcissus) and snowflake (Leucojum vernum), Indian pink (Spigelia marilandica), scarlet sage (Salvia coccinea), daylilies (Hemerocallis), and ferns.

The lovely lavender forms will produce a carpet of spring blooms each year.

Quick Facts and Keys to Success
Common Name: Woodland phlox, blue phlox, or wild sweet William
Botanical Name: Phlox divaricata
Varieties/Cultivars to Look For: Blue/purple: ‘Louisiana’, ‘London Blue’, and compact semi-evergreen ‘Blue Moon’; lavender blue: ‘Clouds of Perfume’; white: ‘May Breeze’ and ‘White Perfume’; and dwarf: ‘Blue Elf’.
Zone(s): 3-8
Color: White, pink, blue, and lavender
Blooming Period: April to May
Type: Native herbaceous perennial
Mature Size: 12-15 inches
Exposure: Part-shade to shade
How to Plant: Propagate by stratified seed in spring or root division and rooted stems in spring or early fall. Plant in humus-rich, fertile, moist, well-drained acidic soil.
Watering: Medium, but is drought tolerant when established.
When to Prune: Cut back after first bloom to promote new growth.
When to Fertilize: Occasionally
In Your Landscape: Woodland phlox is an excellent addition to add color and fragrance to a natural shady bed or a butterfly garden.

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