Blooming all summer long, Diamond Ball has double, icy whitish- blue, 4-5 flowers that bloom on both old and new wood. The vine only grows 5-6 long so its ideal for a trellis where it can climb and show off its spectacular beauty. Clematis Diamond Ball is a vigorous grower and disease resistant. In the early spring, simply prune to 18 tall. It will reward you with stunning flowers the whole season long.