Bleeding Deciduous Trees - Which ones are they and when to prune them

Bleeding Trees - When to Prune

A lot of deciduous trees can be pruned and shaped during their dormant period in winter, but there are some exceptions to this rule. The bleeders.

Trees that release abundant sap ("bleed") from pruning wounds, especially when cut during high sap flow periods
Bleeding sap contains sugars, water, minerals, and plant hormones
Bleeding is natural but can stress trees and invite disease or pests if excessive

Acer spp. (Maples)
Betula spp. (Birches)
Juglans spp. (Walnuts, including Juglans nigra - Black Walnut)
Salix spp. (Willows)
Ulmus spp. (Elms)
Fraxinus spp. (Ashes)
Gleditsia triacanthos (Honey Locust)
Robinia pseudoacacia (Black Locust)
Cornus spp. (Dogwoods)
Magnolia spp. (Magnolias - deciduous forms)
Platanus spp. (Plane trees, London Plane)
Cercis canadensis (Eastern Redbud)
Aesculus spp. (Horse Chestnuts and Buckeyes)
Pyrus spp. (Pears)
Malus spp. (Apples)
Prunus spp. (Some species like cherries can bleed, but are more resistant to pruning wounds)

Bleeding is highest in late winter and early spring during sap rise and growth preparation
Sap pressure builds with warm days and freezing nights typical of this period
Cuts made during this time can release large amounts of sap

Avoid: Pruning in late winter and early spring in order to minimize bleeding.
Best time: Early to mid summer when trees are slowing down their growth and sap flow is lower.

Located 10km southeast of Ballarat at 500m elevation, we understand the seasonal timing challenges for pruning deciduous trees in cold climates.

Visit Navigators Nursery for specific advice about pruning timing for your particular trees and local Ballarat conditions.