Creeping phlox (Phlox subulata) produces thick, prostrate mats of coverage for areas that other plants find hostile. They thrive in rock gardens and graveled paths, where they are often subjected to foot traffic. You can’t beat this plant for sheer beauty and grace as it cascades over steep embankments and stone walls. As tough and durable as it is pretty, this United States native is cold hardy in U.S. Department of Agriculture plant hardiness zones 3 to 9. Creeping phlox requires little care and maintenance throughout the year, including the dead of winter.
Nip the stem tips of creeping phlox with clean, sharp shears when the blooms are spent throughout the growing season. This will keep the plants looking tidy and encourage a fuller habit.
Prune creeping phlox plants back by at least half in mid to late summer after they are finished blooming for the year. You can safely clip them back by as much as one-third if you wish. This promotes vigorous plants and increases natural pest resistance.
Feed these plants a light application of a liquid balanced fertilizer following pruning. Dilute the product to about half strength. Follow the packaging instructions.
Spread a 1- to 2-inch layer of organic mulch such as grass clippings or pine needles over your creeping phlox plants for the winter. Do this just after the first ground freeze in your area if you live in USDA zones 3 and 4. Mulching will insulate the root systems from harsh winter cold and help retain moisture throughout the season. Allow snow cover to remain on creeping phlox as a natural insulator. Don’t mulch these sturdy plants during the winter in warmer climates. They’ll fare much better without it.
Cover the organic mulch with a 1- to 2-inch layer of evergreen boughs, if possible. This loose covering will allow for good air circulation while adding a thin protective layer.
Water creeping phlox once every 4 to 6 weeks throughout the winter in the absence of precipitation in warmer areas. Soak the area thoroughly to evenly moisten the soil surface. In colder climates, water every four to six weeks during dry periods whenever the surface ground thaws enough to soak up water.
Things You Will Need
- Clean, sharp shears
- Liquid balanced fertilizer
- Organic mulch such as grass clippings or pine needles
- Evergreen boughs