Clematis x 'Asao'

[CatherineW]

I am trying to determine if this Clematis 'Asao' is a type A, B, or C. It is battling clematis wilt and I have cut it down to the ground for the past two years. It comes back full and beautiful...then wilt takes over. It is suitable for full shade and growing on the NE corner of my home. I am giving it one more year. Does anyone have a source for information on this cultivar?

[IntrepidMeredith]

Asao is a Large Flower Type of Clematis, and all the Large Flower Types are, unfortunately, susceptable to the disease called Clematis Wilt. A quick internet search gleaned the following information from the Brushwood Nursery website: "When a vine is infected, one or more stems mysteriously wilt and die. If this happens, cut several inches below the dead stem or stems with sanitized pruning shears and landfill all of the debris. If the entire vine is infected, trim it to the ground. This is one of the reasons they should be planted deeply. New buds will arise from the crown underground. If you continue to have problems with Wilt or live in an area known to be badly affected by it, consider many of the fine species like the viticellas, alpinas and montanas. They are highly resistant to Clematis Wilt."
Also, Asao seems to be a Type 2 clematis; in late winter or early spring (before new growth begins), cut the stems back to a pair of strong, well-developed buds (ususally found about 1-2 feet from the end of the vine). You can trim out any crowded or damaged vines at this time too.