How to Divide Coral Bells. Coral bells, which are also known by their botanic name "Heuchera," are one of the best plants you can add to your garden. These perennials come back year after year in Zones 3 through 9, grow in sun or shade, and their pretty scalloped foliage stays evergreen throughout the winter. The plants produce delicate spires of bell-shaped flowers in summer, but their gorgeous, colorful foliage steals the show. Cultivars like "Black Beauty" and "Velvet Night" have deep purple, almost black, foliage, while the leaves on "Lime Ricky" are bright green. Newer peach foliage heucheras, including "Peach Flambe," add a bright jolt of color to beds. One of best things about heucheras is they are easy to divide-which means that you can add more plants to your garden without spending a dime at the nursery. Here's how.
Heucheras grow from a fibrous root system that gradually expands each year. You can divide the clumps after they have tripled in size (usually after two seasons). The best time to divide is in fall, because the plants' roots will have time to grow and establish before the hot, stressful summer months.
To divide the plant, you must first dig it up. The best way to do this is to sink your spade into the ground about 6 inches from the edge of the plant. Pull back on the shovel to help loosen the roots. Repeat this process until you have dug around the entire plant.
Once the plant is really loose, shove the spade underneath the rootball and leverage it up out of the ground. Be sure to lift the plant out of the hole by its root ball, rather than grabbing the plant's foliage and yanking it out of the ground.
Use pruning shears to cut out any ratty or dead foliage. Then, cut the plant into chunks using a sharp, serrated knife (I like to use a Japanese gardening tool called a hori-hori knife). Each chunk should be at least 4 inches wide and have a nice clump of roots attached to it. Discard any dead or weak parts of the plant.
Replant the divisions in your garden or share the extras with friends. To plant, dig a hole that is twice as wide, but just as deep as the division's root system. Nestle the roots into the hole, double check to make sure the crown of the plant (where the leaves emerge from the roots) is even with or slightly above the soil line and then backfill the hole. Water the division in well.