Plant Profile: Creeping Phlox (Phlox subulata)

A Favorite Spring-Flowering Ground Cover

tulips and phlox
David Beaulieu

Creeping phlox is a familiar spring-blooming creeping plant that is frequently seen in rock gardens, growing from crevices in stone walls, or planted as a ground cover to blanket areas of the ground.  Surely the best feature of creeping phlox is its flower production. Not only are the individual blooms pretty, but there are also so many of them that the display is truly something special to behold.

The flowers are so densely packed that it can be hard to make out the plants' foliage from a distance; once blooming is completed, the tiny leaves remain green for much of the year.

Description

In spring, creeping phlox plants produce small, fragrant flowers in dense clusters. The colors available are red, white, blue, rose, lavender, purple, and variegated, in addition to the signature pink color. Creeping phlox plants reach, at most, 6 inches in height and can spread out up to 2 feet to form a mat across the soil surface. Some of the needle-like or awl-like foliage remains green throughout the winter. 

plant that attracts butterflies, creeping phlox is a splendid choice for butterfly gardens. Luckily, deer are less likely to eat this plant than many others, qualifying it as a relatively deer-resistant ground cover.

Botanical Information

Creeping phlox  (Phlox subulata)  is a herbaceous perennial plant related to the familiar upright garden phlox (P. paniculata).

Creeping flox is sometimes known as "moss pink" or "moss phlox," based on its growth habit.  Indigenous to eastern and central portions of the U.S., this perennial ground cover can be grown in USDA plant hardiness zones 3 to 9. 

Landscape Uses

Since creeping phlox plants stay short and spread easily, they are widely used as ground covers.

Although homeowners with flat land can use creeping phlox plants as ground cover to form plant borders along lawns, etc., their dazzling spring flower display is most easily appreciated when they are planted on slopes so they can be seen. These colorful, low-growing plants not only help prevent erosion, but also blanket the slope with vibrant color in spring.

A slope that faces in a southerly direction is ideal, since these perennials do grow best in full sun. If your slope has a retaining wall installed at its base, the plants will spill right over the top—a truly wonderful look. This flowering ground cover is also often used:

The plants' ability to spread over time will be appreciated by gardeners who need a ground cover that will fill in an area. But this trait is a double-edged sword, since other gardeners prefer well-behaved plants that do not spread out. All in all, it is among the best perennials to grow in sunny areas.

Caring for Creeping Phlox

Creeping phlox plants do best in full sun and in evenly-moist but well-drained soils rich in humus or compost. The plants do fairly well in clay soil.

 

After the blooming period, shear the foliage of creeping phlox plants back. This pinching will encourage foliage to become denser, thereby making your plants a more attractive ground cover for the summer months.

If you wish to propagate creeping phlox plants through division, divide them in spring, immediately after they are finished blooming.