Get Three Perennials for the Price of One!
Dig and Divide

Dig them up, chop into pieces, and replant. By dividing your perennials, you'll not only get more (free) plants, but — harsh as the process sounds — your perennials will actually appreciate it. In fact, most perennials grow best when divided every three to five years. You'll know your perennials are ready for dividing when flower size diminishes and the center of the plant becomes brown and dead.

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