When it comes to trees, it’s rarely a good idea to part them from their leaves. The primary purpose of a leaf is to gather sunlight which it converts into food through photosynthesis. Removing leaves from a tree will restrict its feeding ability, so it’s better to prune deciduous trees between late autumn and early spring while they’re dormant. We suggest pruning most deciduous trees before any new growth begins, as pruning after this point may limit that year’s potential growth.
However, as with most rules, there are always exceptions. It may not be evident, but tree species such as Birch, Walnut and Maple begin their growth during early winter. Sap within these trees starts to rise, and if cut, they’ll “bleed” extensively. Sap bleeding will lead to hydration loss and prevent the wound from healing, leaving the tree vulnerable to pests, disease and fungi. Summer to mid-winter is the best time to prune Birch, Walnut and Maple.
Also note: Prunus species, such as Cherry, depend on the production of gum or resin to defend against wound-related pathogens, so you should only carry out pruning in the summer.
Where evergreen trees and hedges are concerned, the rules differ significantly. Trim or prune an evergreen hedge or tree in the autumn, and they’ll have no chance of renewing their leaves before winter hits. With a lack of leaves, they’ll struggle to maintain their energy levels through this period, making them more susceptible to pests, disease or decline. We recommend pruning evergreen trees and hedges in March/April before they produce new growth. Spring pruning allows them to recover before winter and gives them the best chance to stay healthy.
At Guildford Tree Surgeons, our experienced arborists have extensive knowledge of when and how to prune trees to ensure their health and beauty for years to come. For further information, visit our tree pruning services page or contact a team member; we’re always happy to help.
Generally speaking, you should avoid pruning trees when they are in leaf and when the cuts/wounds will be subject to severe conditions such as frost, drought and periods of fungal sporulation (Autumn).