Perennial Gardening - How To Divide Perennial Plants

By Marie Iannotti, About.com Guide

Keep pulling on the handles until the plant has completely split into two plants. If the resulting plants are a good size for replanting, meaning not so large you'll have to divide again next year or so large that they don't fit into the space you've allocated, you are done dividing and ready to replant.

If you have an extremely large plant, you may have to divide it several times before you have new plants of an appropriate size. Simply repeat the steps above.