Answer: In my experience this plant can be very touchy so I would not recommend dividing it. The more common propagation method is by tip cuttings taken in mid summer. Also, you may want to grow this plant for a full season before you decide to plant it over a wide area. It has an unfortunate tendency to protest hot and humid summer weather by dying out in the center, turning black in spots and partially defoliating. My other concern is that although it is considered winter hardy into zone 6, much of the Pittsburgh area is zone 6A or the coldest part of that zone. Depending on your microclimate, it may be as cold as zone 5. So it may or may not be reliably hardy for you. I hope it does well in your garden -- that blue is just so amazing!
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