Regardless of whether the plants die back with the first freezing temperature or first frost, they will need to be cut back in late spring to improve growing habit. If the plants freeze to the ground, you can simply clean up the residue. However, if they are one of the evergreen or deciduous varieties, then they should be cut to the ground in early spring just prior to the beginning of new growth. Perennials are usually dug and divided in the season opposite of their bloom season; spring bloomers in the fall and fall bloomers in the spring. Contact your local Extension office for more information on Asters in you area.

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