Late summer is a good time to prune hedges after they have made most of their growth. Hedges are generally sheared because we want them to grow thickly and have geometrical shape. It is important to prune upper shoots more than lower ones. Not only do they grow faster, but if the top of a hedge becomes wider than the bottom, it shades the lower leaves. Plants drop leaves which are heavily shaded because they are not efficient in producing energy for plant growth. Hedges should be tapered so they are slightly narrower at the top than at the bottom. This will keep them full and leafy at the bottom.