Hi Gayle. I use only bark mulch up here in Massachusetts at about 3-4 inches depth year-round. You shouldn't need too much winter protection there, other than some bark mulch which insulates and helps to keep the moisture level constant in summer. Clematis love bark mulch ! Clematis are very hearty during most winters up here so you needn't worry much down in zone 8. The best advice I can give to you is to water, water and water again during your hot summers.
Fertilizing is important, too. I use Espoma 'Rose Tone' organic granular fertilizer in early spring, before new growth begins, then again after the bloom. Any good granular rose food should do well for you, since clematis and roses are similar in all their needs. A shovelful of manure or two on occasion is also a nice boost to the soil, but I don't like to touch the vines , so I spread it around the root base.
Prune your clematis in late winter before new growth actively begins according to each pruning group. If you do these things and water well in your hot, dry summer you should have gorgeous clematis. I'm sure others will give their own good advice as well, but the above is just what I personally do and it has been the best method I've found yet for a strong, lush clematis bloom year after year.
Good luck.
Suzy

Gayle, I do nothing as far as winterizing my clematis in my NC garden. I do use a wide variety of mulches year round including grass clippings, hardwood mulch, and pine straw. I have always mulched right up to the stems with the mulches I use and never had any problems with rot or anything similar. Mulch is mulch to clematis and in our hot summer weather, any is welcomed by the clematis. As Suzy said, water is critical during our hot summer months. I can't tell you how many times I dragged the hose around the yard this summer. As for fertilizer, I use whatever is convenient be it granular time released synthetic fertilizer, compost, compost tea, alfalfa pellets, grass clippings, etc. Consistent moisture, mulch, and fertilizer of any sort as long as it is not a direct release type and as long as it doesn't contain a high percentage of nitrogen is what is key to getting your clematis to grow strong and produce blooms. Good luck!

Gayle, one other thing I forgot to mention earlier. I see from your zone 8 information that you are most probably located in the eastern part of the state and most likely have a much sandier soil than I do. If your soil is sandy and drains well, you need to make sure you incorporate a lot of organic material in your soil when you plant your clematis and continue to add it to the top of the planting area on at least a yearly if not biyearly basis. Sandy soils in the eastern part of the state drain rather quickly and don't hold water. The result is that you have to water much more frequently and your clematis will resent the soil drying out. With the added heat in your part of the state, this will only exacerbate your sandy soil situation.
There are also things you can do to make your clematis bloom better and hold up longer in your area. Plant clematis on the eastern and northern side of your home to give them relief from the hot afternoon sun. Those clematis you do plant in full sun should be in the group III category and the viticellas are ones that would do best in that westerly situation. Once again, good luck!

Thank you for your info! I do add lots of compost, manure etc to build up our soil. We are approx 60 miles from the coast but still have clay and sand! I remove the soil in most new beds and use a portion to mix with the compost, new topsoil, manure etc to refill! I definitely need to add more Group III! Probably the thing that I need to do a better job of is consistent watering! I do feed but need to water more frequently! Thanks again!
Gayle