When to prune leylandi?

Leylandii should be pruned in late spring or early summer, typically between May and July, to encourage healthy growth and maintain their shape. Pruning during this period helps avoid damaging new growth and minimizes the risk of disease. It's also essential to avoid late summer or fall pruning, as this can lead to frost damage on fresh cuts. Regular maintenance throughout the growing season can help manage their height and density effectively.