Westy, it sounds like clematis wilt and a coincidence of an insect laying eggs on the stem. I recently had to cut back two clems due to wilt. I also have been seeing the white powder and a little grey/white triangular bug in the same bed laying eggs on my hosta flower stems. Tis the season. When those eggs hatch they will munch on whatever they have been nested on. Wipe it off with a damp rag and then give it a spraying of soap and water to make the plant less tasty to eat. I sprayed my lilies last year when the same nest appeared and it worked well. 1 TBSP of dish soap to a quart of water in a hand sprayer is the amount you need. This also worked well with japanese beatles.

Good luck,

Tracy

I thought I had a mystery Clematis failure with a vine planted this Spring until the Armillaria (honey fungus) mushrooms appeared in the pot. So I duly decided that the fungus had gotten the Clematis, even though the Japanese Maple in the same container is just fine, and even though I've observed Clematis doing just fine in other areas of my garden next to honey fungus colonies. It turns out it wasn't wilt, wasn't fungus, wasn't bugs (well, not directly): It was rampaging kitten CHASING bugs and tearing up the vine as he raced after the bugs. The reason the Clematis in the other container (also containing a Japanese Maple) is doing okay is because there's a pot of cane begonias blocking his route through the Clematis.

Tracyvine - are you saying that you spray your plants with your dishsoap mixture and it has deterred Japanese Beetles? They're a real scourge in my garden and I'd be interested in anything that might help. What kind of dishsoap do you use and how often do you respray it?