Is there a recommended time of year to cut back the hedge so that you get the benefit for the longest period of time?
Escallonia hedges. Escallonia can be trimmed in May and again in late August if you want a formal hedge without flowers. For an informal, flowering hedge, cut after flowering in June. Hard prune in the spring to reduce its size.
Beech and hornbeam hedges can be pruned in August. They grow rapidly in the early part of the year, but need to grow a little after cutting to make sure there are no bare patches through the winter. If the hedges have grown too large, cut back hard in mid-winter, avoiding very cold spells.
Winter or spring is ideally the best time to cut back and trim hedges.
Either end of the season. So October, November depending on weather. Or before the new season Feb, March depending on weather