Cold hardiness is developed by the pattern of progressively excursions to colder temperatures. Judging by Newark = New Jersey, you could put them outside now and they will likely be just fine. Overnight lows are 40-ishF, though it did get down to 28F a few days ago. What is damaging is sudden cold like being in balmy 50Fs and then 20F that night. This is bad for just about everything. If you see it coming, bring it in overnight, otherwise .they'll be fine outside.
Nice to see someone else with them.. The neighbour had a mature wisteria next door, I took seeds 3 years ago and been growing them ever since. My ones were grown in a small seedling tray on the window sill. They were upgraded to bigger pots afterwards then I simply danced them in and out of the house, 1 warm day outside, inside at night, out, in, out out, in, out out, in, out out out... etc. Adjusting to the weather but obviously if the timing is now that its winter and they've never been outside, in my climate, I would have kept them inside till Spring. No point risking anything, unnecessary. Then start the dance in Spring.
My biggest one in the ground for a year. The ground really accellerated things.
DSC_2537 by Conor Dashwood, on Flickr