How to Divide Phlox
- 1). Plunge your spade into the ground next to the phlox and pry it up. You may have to break the soil on more than one side of the plant if the soil is hard; you want to avoid pulling so hard on one side of the plant that you rip off the roots.
- 2). Cut the bundle of roots into two or three clumps, depending on the size of the plant. Preserve the green shoots.
- 3). Re-plant one clump in the original hole. Loosen the soil at the bottom and sides of the new holes and plant the other clumps in these holes at their original depth.
- 4). Mulch the plants, if you are dividing them in the late summer or fall. Though phlox are hardy, newly-divided and planted clumps need extra protection for their first winter. Iowa State University recommends 4 to 6 inches of straw or pine needles. Leaves would also work well.
- 5). Keep the newly-divided plants well-watered for their first summer.
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