First, it takes six or more years for these vines to reach reproductive maturity. If these vines were severely pruned, expect flowering to be further delayed because it encourages the production of rampant vegetative growth at the expense of reproductive growth. Second, could the vines have been winter-killed? Though Actinidia arguta and Actinidia kolomikta are hardy to Zones 4 and 3, respectively, they don't achieve complete cold hardiness until they are a couple of years old. Without winter protection during their early years, the top growth can be killed, resulting in the same response as heavily pruned plants. Third, excessive fertilization with nitrogen will result in the production of leaf growth at the expense of flowers. Finally, A. arguta should be placed in full sun or partial shade and A. kolomikta in partial shade. Inadequate sunlight will affect flower bud production.