Hi! I'm new to the site, and have long been wondering who I could ask to help me identify this clematis. I've done a bit of poking around online at various nursery sites hoping to find it, but I'm a little overwhelmed by how many varieties and species are available. A relative bought the plant a few years back but she can't remember where. She regrets her purchase now, because it's such a vigorous vine. It topples obelisks and scrambles underneath the siding boards on the house. I've basically inherited it now (or rather rescued it on its way to the compost heap), and would like to know which species and group it is, if anyone has any idea. I'd love to know the variety too, but maybe that's too much to hope for. I'm fairly new to ornamental gardening, I usually just grow edibles, but I didn't want to lose this lovely vine, and want to know as much about it as possible. This picture is of the first flower of the year, which opened April 2nd (I'm in the South Eastern US, zone 8 if that is important to know). The back sides of the petals are a slightly paler purple with green stripes, and the flowers have 8 petals and are about 6" in diameter. Previously, the plant has been cut down to about a foot of growth every year, and it always comes right back in spring. I'm curious how tall the plant will likely grow to, so I can provide it with an adequately tall and stable trellis. I appreciate any help that anyone can give me. Thank you!