I've just planted a Clematis in a container. The reason for this is that a propane gas pipeline runs right underneath where I want it to be and I'm a bit nervous about digging around the gas line - or letting a vigorous plant establish roots around it.
Now so far (about 6 weeks) its grown really well - made a whole lot of new growth and taken off up an improvised trellis of garden canes and string.
What I'm wondering is - will the Clematis thrive in a container in the long term? Will there come a point where the roots have nowhere else to go and the plant will die? It's a good big container - about 2' by 2' by 2'. I'm keeping it well watered and have put some slates on top to shade it from direct sun. (I understand they like their roots cool)
Any thoughts folks?