Clematis can take a year or two to get established and are very greedy so I would give it a good general purpose feed next spring to get it growing well and add special rose, tomato or clematis fertiliser to promote flower production. That will help the Kiwi too and you can top up every couple of weeks till mid June.
It's a myth about clematis needing their head in the sun and their feet in the shade. I've grown them in hanging baskets before now and have some planted in full sun as well as others in shade or semi shade. Some varieties like shade and some like full sun and they all like a deep root run and plenty of food.