I agree with Janet and as she well knows I have beating this drum for several years now. The old adage of heads in the sun and feet in the shade is an old wives tale. Moisture is what is required and that typically occurs when the roots are shaded since it slows down the evaporation of the water in the soil and the consistent moisture is the critical element, along with appropriate fertilization. For what it is worth, I have potted up countless numbers of clematis into one gallon sized pots and left them in the sun where they get morning sun thru midafternoon sun and they have been fine. One definite advantage of sinking the pots in the ground is that you won't have to water the pots as much since the soil will act as an insulator to the desication of moisture from the potting mix. Just make sure that the surrounding soil drains well or your pots could hold too much moisture and cause root rot.

Sorry for delay again but don't have access to computer on a daily basis :-) No doubt the topgrowth of the vine would be fine in zone 6.....it is just the root system I'd be concerned about. Roots are much more vulnerable to cold damage. If the plant is in the ground, it is not really an issue as the surrounding soil mass is adequate insulation. But the roots in a container don't have that benefit. And sometimes (maybe often), the roots actually come into contact with the container wall and almost direct exposure to cold air temperatures. You could keep the pot outdoors but you will need to provide some additional protection. If you can slip the clematis container inside a larger container and then stuff the open space with crumpled newspaper or what have you, that should help. Or wrap with bubble wrap. If the temps look like they will drop into the low 20's (really anything below 25F) for any length of time, you may want to bring the container indoors. Just get it back out as soon as possible.

Now is not an ideal time to prune. Colder weather later in the season could very well damage wood exposed by this late pruning and increase winter dieback. I'd wait until late winter/early spring after the worst weather has passed and examine for truly deadwood then and remove. Nikko Blue behaves rather idiosyncratically compared to most macs and will often produce blooms despite rather severe pruning. Regular fertilizing, as is necessary for any containerized plants, may encourage more flowers. As to the look of the plant from the photos, if these were taken any time recently, I am confused as to what you are worrying about. It looks great, all things considered. It is the first of November afterall and even here in the rather mild PNW, most hydrangeas are looking pretty crappy - even more so now that we have just experienced our first hard frost. The only ones that look the slightest bit decent are the oakleafs which are in full fall color and hold their leaves well in cold.

The ones leafing out and shiny tips are the ones I got from Aloha. They've been in the bottles for 4 weeks now. No visible roots yet, but I don't touch them or pick them up to see. I have them in 5 gallon pots, 4 bottles to pot. However, the ones I got from Derrick have only been in the bottles for a week---and I just ordered 12 more. LOL I'm figuring doing the heat mat for them. I have a room with sliding glass doors facing south so they would get sun daily (at least when the morning overcast clear up). Of course, here is SoCal we still have maybe a couple more months of 70 and 80 degree temps so they may just get started before having to bring them in. Trying to get a jump on next spring. :)