BOX HEDGES and topiary need an annual trim and the best time for this is between now and the end of September. Topiary needs a careful eye. Most of the best exponents of the art use hand shears rather than mechanical trimmers. Holly makes more uncomfortable topiary but, as with box hedges, it 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 as a guide.
IF YOU have not already done so, now would also be a good time to thin out the old wood of philadelphus. Do not prune by shearing over the whole shrub. If you do, you will remove the new wood which will bear next year's flowers. On the other hand, if you do nothing the shrub will grow too large.
BUSHES OF santolina (cotton lavender) become open and leggy with age. As soon as it has finished flowering, cut hard back to encourage new growth from the base. Unlike lavender, which is loath to sprout from old wood, santolina will and it will look much better next year if treated harshly now.Reuse content