Are you sure it is a something that is eating the roots? Other than gophers or voles, I'm not sure what that would be............not anything I have encountered in many years of growing clems :-) And in a pot, I would think access to voles would be very restricted.

How do you plant the vines? What's your soil like? Poor drainage or heavy clay soils could certainly restrict root development and could lead to root rots.

Photos of the dead clematis? How do you water if at all? What is the soil like? Do you actually see holes in the soil? Do you have slugs, which will eat the plants off at the base.

I do have voles that eat the roots of in-ground clematis if they aren't protected, so I plant them in large 8" deep cylinders of 1/4" hardware cloth that are a bit over a foot in diameter.

Ty, I will try this. And I will continue to seek out the problem, it must be gophers or voles they do leave round holes in the dirt right beside the missing plants. The one vine I planted in a pot is still making it but it does not look real healthy. I have put out spray to get rid of the gophers and voles. Cross our fingers. Ty y'all very much for all ideas. I hope I will be able to one day grow healthy clematis vines.

Round holes (about 1" diameter) sound like one of my two species of voles. I put my hardware cloth cylinders so they stick up about an inch above the ground to keep them from burrowing in from the top. It does mean I don't garden barefoot since they hurt like the dickens to accidentally step on!

Found the photos of my cylinders. 1/4" hardware cloth wire mesh, cut from 36" wide rolls and overlapped slightly and "sewn" closed with wire makes a cylinder between 11"-12" diameter. I cut off strips 8" high with tin snips since it is easier than standard wire cutters. The smaller on on the right I would use for a smaller perennial, not clematis.

I have also started trying plastic mesh to see if it works as well since it is much easier to work with and can be cut with scissors. It is also less likely to stab me as cut wire ends are painful.