Non chemical control
Canker is said to be more serious on wet, heavy and/or acid soils, so pay attention to drainage and raise the soil pH by liming if needed.
Completely cut out all affected smaller branches and spurs. With the larger branches, try to cut out all infected material. All such pruning should remove all brown, infected bark and wood, cutting back to fresh green tissues. Paint immediately with a protective wound paint such as Medo, Growing Success Prune and Seal or Arbrex Seal and Heal, to prevent the wounds becoming reinfected.
Inclusion of a product does not indicate a recommendation or endorsement by the RHS. It is a list of products currently available to the home gardener.
No variety is completely resistant under all conditions, but the following all show some resistance: ‘Alfriston’, ‘Annie Elizabeth’, ‘Brownlees Russet’, ‘Cockle Pippin’, ‘Crawley Beauty’, ‘D’Arcy Spice’, ‘Emneth Early’, ‘Grenadier’, ‘John Standish’, ‘Katy’ (‘Katya’), ‘Lane’s Prince Albert’, ‘Lord Derby’, ‘Merton Russet’, ‘Newton Wonder’, ‘Orleans Reinette’, ‘Reverend W. Wilkes’, ‘Rosemary Russet’, ‘Winston’.
Some varieties are particularly susceptible to canker and these include ‘Cox’s Orange Pippin’, ‘Lord Suffield’, ‘James Grieve’, ‘Ribston Pippin’, ‘Worcester Pearmain’, ‘Ellison’s Orange’ and ‘Spartan’.
Apart from the wound paints described above, no products are available to gardeners for the control of apple canker.
Fungicides for gardeners (Adobe Acrobat pdf document giving further details of wound paints available to gardeners)
Chemicals: using safely and effectively
Chemicals: storing and disposing safely