The mauvy pink flowers of Clematis Comtesse de Bouchaud (often misspelled as Bouchard) are just so beautiful with their crepe georgette texture and are produced over a long time from late Spring to late Summer. Planted at the base of the hedge of Viburnum tinus behind the the North facing picket fence, gives it the ideal spot with its ‘roots in the shade and head in the Sun’.
If you don’t have a similar position you can keep clematis happy by using thick mulch to keep its roots cool and moist.
Confusingly I have seen this particular clematis classed as both a Group 2 and a Group 3 Clematis. Group 3 Clematis require hard pruning, by cutting back to a pair of large buds around 30cm from the ground in late Winter or early Spring. Group 2 Clematis are usually not pruned back in Winter, but just pruned back by half after the first flush of flowers. Being a combination of both 2 and 3 basically this means that you can prune the Comtesse as either or as both. You could hard prune all the stems except for a few and that would mean that you would get earlier flowers, and then also after the first flush prune her back about half way to encourage a second bloom.