Box hedges and topiary need trimming only once a year. This month or the next is the best time. Topiary needs a careful eye. Most of the best topiary artists use hand shears rather than mechanical trimmers. Holly topiary is awkward to work on, but as with box should be clipped to shape this month.
Established hedges of beech should be trimmed now. If you do not have a good eye for a straight line, stretch a string along the hedge to give you a guide.
If you have not already done so, thin out the old wood of philadelphus. But do not prune by shearing the whole shrub since this will remove the new wood that will bear next year's flowers.
Bushes of santolina (cotton lavender) get open and leggy with age. As soon as the plant has finished flowering, cut hard back to encourage new growth from the base. Unlike lavender, santolina will sprout new wood and it will look much better next year if you give it harsh treatment now.Reuse content