Veitchii Lacecap Hydrangea. 'Veitchii' is my favorite white lacecap. It is a large vigorous grower reaching 6', but my reasons for favoring this plant are twofold: 1. it has some the best mildew resistance of just about any Hydrangea known and 2. it has some of the bluest true flowers which contrast so well with its white sterile florets. If pruning is needed, do it immediately after flowering as the plant will have time to put on new growth that will set flower buds for the following spring. So that flowering is not affected, try to prune at or before early August.