Dividing your perennials will increase your garden stock and rejuvenate older plants, keeping them vigorous and blooming freely.
Most plants should be divided every three to five years. Dig and divide coneflowers, garden phlox, foxgloves, Shasta daisies, day lilies, coreopsis and other spring/summer-blooming plants in the early fall to enable their roots to become established before winter.
Ten easy division steps to follow are:
- Lift the plant to be divided, taking care not to damage the roots.
- Gently shake off loose soil and remove dead leaves and stems.
- Separate plants using your hands, a garden spade, fork, or knife.
- Discard the center of the clump if weak and woody.
- Divide the vigorous plants into clumps of three to five shoots each.
- Bearded irises should retain a few inches of rhizome and one fan of leaves, trimmed back halfway.
- Prepare your garden soil by adding compost, peat moss, or aged manure, along with a light application of super phosphate or bone meal.
- Replant the divided sections to their original depth.
- Label your new plants and water thoroughly.
- Apply winter mulch after the soil temperature drops following several killing frosts.
Robin Wright Brumbelow, Smith County Master Gardener
Texas AgriLife Extension Service