When To Transplant Creeping Phlox

Creeping phlox (​Phlox subulata​, USDA zones 3-9) is a low-growing, ground cover plant that carpets any sunny field. In spring, its dense, delicate foliage is topped with a profusion of fragrant flowers in white, blues, purples or pinks. This herbaceous perennial spreads fast and is an easy-care creeper that doesn't require much gardener effort. If you have a little phlox and want more, you can use the easiest of the phlox propagation methods to "build" more phlox ground cover: dividing or splitting creeping phlox.

You've seen creeping phlox, that flowering ground cover that seems to froth through the cracks in stone fences or up the retaining wall at the base of your sloping backyard. Creeping phlox is also called phlox moss, thanks to its dense, compact growth pattern. Since it is naturally short, no taller than 6 inches, and spreads fast, it is perfect for a carpet for your backyard, or even an adjacent rocky field.

Phlox is at its most ornamental in springtime, when its tiny green leaves are covered by showy flowers. They not only light up the area with the bright colors, they also fill the air with a sweet fragrance. To maintain the compact ground cover through summer, gardeners shear the plant by half after flowering.

Creeping phlox isn't one of those super-expensive plants, but if you want to create another area of ground cover, you'll need more than one little starter plant – and costs can add up. An easy and inexpensive way to proceed is to propagate the phlox yourself instead of buying dozens of starter plants. But you'll first have to pick a phlox propagation method.

Obviously, creeping phlox can propagate from seed. In fact if you have a healthy, happy bed of phlox, they will reseed themselves freely. But that isn't the only way to get more phlox plants. You can also clone your creeping phlox plants by taking phlox cuttings after the plants are finished flowering. Clip off sections of phlox plant stems some four inches long, making sure to make each cut just below a leaf node. Dip the bottom end of each cutting in a rooting hormone and plant in a well-drained growing medium.

The easiest of the phlox propagation methods is called division. To accomplish this, you essentially dig up a plant, separate it into several sections, then set each in a new location. This not only gives you new plants, but also aids the old plant by eliminating overcrowding and providing the roots more room and resources. You'll want to tackle this task in spring, just after the blossoms have finished their show.

During division, dig out a section of the mat of creeping phlox. After a part of the plant and its roots are exposed, sever it with a sharp spade or shovel into two or more plant sections. Be sure to keep the roots intact and attached to the foliage section of the phlox. Each section can be treated as a new plant, to be transplanted to a new location. There it will grow and spread to cover bare land.

When you are doing the transplanting, install each section of the creeping phlox in a new planting hole slightly wider than the existing roots. Bury the roots under the soil and leave the foliage above the soil. To make it easier for the new divisions to take root, dig up the soil and the bottom of the hole before planting, and provide water.