Barb, there are some people who can grow montanas in zone 5 and have posted some wonderful pictures of them. The issue with them in the colder zones is that often the plant can freeze back to the ground each winter or the flower buds will be frozen and not develop. Since montanas bloom on old wood, the result would be a montana that you never had flowers on. As I said, some people in zone 5 do have protected spots or microclimates in their gardens where the montanas do flourish and flower but you would have to find a protected spot that would allow this. Hence my recommendation to steer clear of the montanas. Hopefully one of the people who coplant roses and clematis together will chime in and give you some advice as to what types of clematis will work with your roses. I don't grow roses although I have ordered Ebb Tide for delivery this spring. The bottom line is that if you have to prune your roses back in the late winter/early spring, you would probably want to plant type III clematis with them since they would similarly have to be pruned back and since they bloom on new wood, you wouldn't be sacrificing the clematis blooms by the pruning. If the roses are the type that don't need pruning you could plant type I or II clematis with them since they bloom on old wood and not having to prune the clematis back wouldn't cut off the blooms formed on the previous year's growth.

I doubt that heat is the issue - most LFH clematis (type II and III) are good in AHS heat zones 1-9, which is quite a bit hotter than you are likely to see in Tennessee. And folks grow them in places like Texas and Arizona as well. I would be more concerned about how much water the vines might receive and how deeply they are planted. If they are planted deeply (4-6" above the soil level of most potted clems) and the soil kept evenly moist, they should not be drying out, especially if planted where they receive afternoon shade. You might want to focus on the viticellas or some of the American species clematis. Drying out in the heat of summer appears to be less of a concern with these.

Clematis don't do well as houseplants. I have a Florida Sieboldii that is in a large pot and keep it in my unheated garage for the winter. It was moved to a larger pot this spring which set it back but it is blooming now. No special care in the garage over the winter. I set all pots on pieces of wood to keep pots off cement floor. Some people have had success planting this clematis in certain areas of their yards with micro-climates that allow it to survive in our colder zones. I may buy another plant and try that next year. Have you seen 'Cassis'? It is a dark purple which looks like 'Florida Seiboldi' and is hardy to z:6. Cassis was a new purchase this spring and is potted in a matching pot. It is blooming now. I also have a c. montana rubens that has been overwintered in my garage for several years. It survives but has very limited bloom for me so it will go south with family this fall. Here is a link that might be useful: COW Cassis

We are in a zone 5b/6a. Because we wanted to have fresh figs that we could grow outside with out winter protection. We started testing for cold hardy figs maybe 8 to 10 years ago. At the time, Hardy Chicago was considered the most cold hardy fig there was. Because it was discovered growing in a suburb of Chicago. Which is a zone 5b/6a. But, after testing it here for some 10 years we found it was not. But, that was for our cold zone 5b/6a. With any one trying to grow northern climate cold hardy figs, in zone 6b, a good number of figs for that zone, have been discovered in the last twenty or so years. At the time this information made us very happy. But, that was because we thought we were in a zone 6b. Then we found out that we were not. After watching figs in our collection like Hardy Chicago get top killed. We started all over again, looking for figs that would be successful in our 5b/6a zone. We have some twenty figs in here at our home that we have been testing, for the last 8 to 10 years. We found that there were only a few that could take our cold 5b/6a zone But, for any gardener in a zone 6b, there are about half dozen or so figs that one can grow. I have not figured out how to make attachments to this forum. But, I can send our test results to any one who would like to see what will grow in a zone 6b with out winter protection, If you send to me a email to robertcharper@gmail.com I will attach the list to your return email. Bob Harper