While clematis have traditionally grown up walls, wooden structures, posts and wire fences, there are other ways to use clematis in the landscape. Certainly, the smaller vining and bush types work well in container gardens and rock gardens. They won't overwhelm the other plants. Try clematis on metal trellises as a beautiful backdrop in a perennial garden.
However, let some clematis run wild. Try growing 'Niobe' large flowered clematis at the base of some juniper bushes in your yard. Help the vine get started in the juniper bush, then let it run. It's always a delight in midsummer to see bright red flowers randomly popping out from the juniper bush. Depending on the aggressiveness of your clematis vines, you can repeat this technique on small trees, tree stumps and any open-branched shrub. Growing clematis among evergreens is attractive because they give a nice backdrop to the colorful clematis flowers.
You can even let some clematis, such as Clematis Praecox, run horizontally down a bank or slope as a ground cover. It will flower among the plantings creating a surprising visual effect. Some of these ground cover types are so aggressive they will crowd and shade out weeds. But be careful they don't spread into other gardens.