With its bold, fragrant flowers, wisteria is best cared for with careful pruning, a process that should be executed three times a year. Prune your wisteria after it blooms, again in late summer, and one final time in winter or early spring. Don't hesitate to prune heavily, since it is key to controlling wisteria's growth. Left unchecked, these plants can grow 10 feet a season -- all of it foliage and none of it bloom.
Place wisteria plants in a fertile location, and apply superphosphate to the bottom of the planting hole. Regular applications of fertilizer are not necessary (in fact, they encourage leaf growth while discouraging flowering). Take care when fertilizing grass or other plants nearby -- a nitrogen boost can knock the wisteria out of bloom.