The answer to 'how often to hedge' is that most hedges should be trimmed 1-2 times per year. Hedges like privet, boxwood, and yew typically need trimming in late spring or early summer to maintain their shape and density. Fast-growing hedges like laurel or leylandii may need trimming every 6-8 weeks during the growing season. Trimming in late winter or early spring is best for deciduous hedges like beech or hornbeam.
The ideal trimming schedule depends on the type of hedge, its growth rate, and your desired appearance. Regularly pruning and shaping the hedge will keep it looking neat and healthy. However, be careful not to over-trim, as this can damage the plant. It's best to consult with a local landscaping professional to determine the optimal trimming schedule for your specific hedge varieties and growing conditions.