Perennial phlox is prized for its tall, upright stems adorned with heads of many bright flowers. Bloom colors range from pale pinks and lavenders to deep reds and bright whites. Phlox may reach heights of 2 feet or more, making them a striking addition to borders or a nice background flower for more diminutive flowers in beds. Propagating phlox from your existing plants allows you to enlarge your plantings without the cost of purchasing new transplants from the garden center.
Dig around the base of the phlox plant, taking care not to hit the root with the trowel. Slide the trowel under the roots and lift them from the soil.
Break apart the root to divide, leaving three to five shoots attached to each root section. Inspect each division for signs of disease and cut off the damaged parts with a sharp knife.
Plant each root section in a well-drained garden bed that receives full sun. Prepare new beds by laying a 2-inch layer of compost over the bed and tilling it in to improve soil drainage.
Sow divisions deep enough so the crown of the plant, where the stems emerge from the root, is 1 inch beneath the soil surface. Space each division 18 inches apart.
Water thoroughly after replanting to collapse any air pockets around the root system and to encourage new growth. Apply a starter fertilizer, following label application instructions, to give new divisions the required nutrients for healthy growth.