Answer: The problem with zoysia is that it is a warm season grass. So as the weather cools in the fall, the grass will begin to turn brown, and will be completely brown once frost hits. There are other grasses more suitable for your region, such as bluegrass and fescue.
Here are a few suggestions for ground covers for sun to part shade: carpet bugle (Ajuga reptans), lily of the valley (Convallaria majalis), European ginger (Asarum europaeum), creeping myrtle (Vinca minor)
I hope this helps!
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