Clematis paniculata wont even grow in zone 5, let alone become invasive - it is a very tender species originating from New Zealand.

I believe your question involves Sweet Autumn Clematis, Clematis terniflora, which is often incorrectly referred to as C. paniculata and frequently sold under that incorrect species name. It is a very robust and aggressive species from Asia, that can reseeed freely under the right circumstances. It is considered an invasive species in much of the MidAtlantic states and on into the Gulf Coast and has naturalized (but is not yet considered invasive) across part of the midwest.

Grew it myself for many years where it became a very large, real estate eating vine (even when pruned back hard each spring) but nary a sign of a seedling or any invasive tendencies in my climate. YMMV

Thank you GG.

This is not the first plant purchased this season (from reputable nurserys) that was mislabeled. But like you mentioned, it is common for this plant.

I planted it next to a fence, so it has lots of room to spread. I'm guessing being so far north, it won't become invasive...at least I'm hoping.

Thanks again!

It is not invasive here in Iowa - zone 5. It's a wonderful clematis. I wish I'd get a few seedlings so I wouldn't have to buy more of them every time I want another one!

Good to know...thank you.