Answer: Clematis generally seem to grow slowly and bloom just a little the first two or three years while they are settling in. Improper pruning can reduce flowering since some types bloom on older wood, meaning wood from the previous year and in some cases, they will bloom in late summer on wood grown during the first part of the same season. (This might explain why it bloomed late last summer.) If it bloomed very late last season, you might have a fall blooming variety such as the Sweet Autumn Clematis which blooms in the fall with fragrant white flowers. Basically, the best you can do to help it along is keep the soil evenly moist and use an organic mulch to help keep the root zone cool and moist.
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