QuestionsHow to growTrees and ShrubsPruningclematis tangutica pruning 0 Vote Up Vote Down Alan Stenson asked 15 years ago can i cut back clematis tangutica now in august as it is smothering some other plants like this thuja smaragd in the photo..or will i just wait till spring…i’ve just hoisted it back to expose the other plants 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 7 years ago Clematis tangutica is grown as much for its silky seed heads as its flowers and if you prune now you will cut these away. Leave it until winter.