Under normal circumstances, it will grow to 2-3' diameter at the base, and, as you can see from the photo below, easily 2-3 times that at the canopy.

It probably won't grow to it's fullest potential in your zone 4 climate.

Hey Donn, easy on the zone 4 comments !! :o)
Interestingly enough all my Panicums get just as tall & just as wide up here in my zone 3/4 garden as they did in my zone 5 garden.

Enjoy your grass sunlicious!
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nice pic!!!

thanks for your reponses. i think it will be fine where it is.

i tried miscanthus 'huron sunrise' and another one (slips my mind). they were varieties that some people have had success with in z4, but, mine never came back after first year of planting.

Poor success with the Miscanthus must have more to do with snow cover than zone?? I just looked at a zone map & I really am a zone 4a garden with lows often down to -30F. But, we have good snow cover and I garden on sandy soil. I am growing at least 10 different cultivars of Miscanthus sinensis with no losses over a 5 year period AND I am able to grow Arundo donax which I might add, is very very happy here!

The colder your winters, the more important it is to give plants that might be iffy a really early start. Don't try planting, moving or dividing at the end of the summer.

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