A fast and easy way to make more plants is to dig up an existing mature plant, divide the clump and then replant the divisions. Many perennials are good candidates, including asters, hostas, chrysanthemums, daylilies, liatris, black-eyed Susan, meadow rue and many ornamental grasses.

Spring and summer-blooming perennials are best divided in autumn; divide autumn-blooming perennials in spring. Divide perennials on a cool, cloudy day. If the ground is dry, water the plant a day before dividing.

Use a sharp shovel or garden spade to dig up the plant, keeping the roots intact as much as possible. Gently remove loose soil. Either pull the plant apart with your hands, or use a knife, pruning saw, garden spade or garden fork to cut the clump apart. Each division should have at least a few healthy shoots with a mass of roots attached.

Replant each division in its new location, setting each plant at the same depth as before in a hole slightly wider than the division. Fill in the hole, then firm the soil and water thoroughly. Keep the soil evenly moist until plants show new growth.