Plants usually bloom better if you divide clumps every 3 to 4 years. Lift the entire clump using a garden fork in early spring through mid-fall. The best time is after they have finished flowering. Start by placing the fork in the ground 6 to 12 inches away from the base of the plant. Gently push down on the handle to pry the clump up and out of the soil. Work around the root ball repeating this process until the …