Posted: 28/03/2017 at 13:41
I can't help with the jasmine but I do find that clematis can spend a year or two getting their roots settled before they put on significant growth and flowers. They also need careful planting - deeper than they were in their original pot - and plenty of food and water as they tend to be hungry, thirsty plants.
How and where did you plant it? Deep? In a pot? In the soil?
Clematis montana are classed as group 1 for pruning. This simply means you only prune them after flowering and only if they need to be kept in bounds. A young one should nt yet need pruning but yu may want to guide any new shoots it makes as horizontally or diagonally as possible to encourage extra shoots and flowers.
Clematis generally appreciate a generous dollop of slow release specialist clematis food in spring but rose or tomato food will do. Occasional liquid feeds of rose or tomato food between spring and the end of June will help too.