root systems, such as Campanula,
simply dig up the plant and gently
pull the roots apart.
There's a lot of math going on in every successful garden. Adding new plants. Subtracting weeds. Multiplying your perennial population. And there comes a time for division, too. When plants look overcrowded or cramped, it's time to divide (generally, every three to five years). Or, you can divide to add your favorite perennial to a different spot or share it with a fellow gardener.
Remember: If the plant blooms in the spring, divide in the fall; if it blooms in late summer or fall, divide in the spring (midsummer-blooming plants should be divided in early spring).
Dividing is simple. Follow these tips, and you'll soon be a master at easy division. It doesn't get any easier than this.