The French Pussy Willow, Salix caprea, grows well in almost any soil but it is a good idea to supplement it with peat moss, leaf mold or compost. They require full sun to thrive, but will survive in the shade as well. As with most willows, they do best when given lots of water. Although they can be allowed to grow unpruned, the plant will benefit from regular pruning after blooming.
Prune the lowest branches back to the trunk, and prune for shape. You can even cut the tree back to a six inch stump every 2-3 years (severe pruning results in the longer stems and larger catkins). Flowers form on the previous season's growth, not on new growth so do not prune until the flowers have faded. For early bloom, cut branches of pussy willows may be brought in and set in a water filled vase in a sunny window anytime after the middle of January. The catkins will develop and make a nice display for a considerable time.