Hydrangeas are one of the glories of late summer, and H. paniculata is deservedly fashionable in its many lovely forms. It will excel itself if it’s pruned hard this month. Having left the papery flowers of last year in position for a bit of winter protection, you should now remove them and reach down into the structure to cut each healthy shoot down to the lowest pair of green buds. This apparently tough regime will lead to renewed vigour and a bumper crop of big flowers in due course.