How to Identify and Cure Apple Canker Disease, Neonectria ditissima

Winter is the perfect time to prune your apple tree. But what’s this?! As you are pruning the bare apple tree branches you spot damaged and split bark, and small sunken dark-brown areas with flaky bark. Is this a disease on your apple tree, and should you worry? How do you know if it will kill your apple tree? And what can you do about it?
The cankers on the branches of your apple are most likely apple canker disease caused by the fungus Neonectria ditissima. This fungus can result in apple tree branches dying-back and if it occurs on the main trunk then it can kill even kill your apple tree. If you look closely in the winter you should be able to spot tiny red spheres on the surface of the canker. These tiny red spheres, which I show you in this video, are a great way to confirm apple canker infection and they allow the fungus to complete its life cycle over the winter.
I show you how to recognise early stages of apple canker infection, as well as the more developed older cankers. I also give you advice on how best to prune your apple tree to avoid infection with apple canker fungus. In the UK there are no fungicide spray applications available for home gardeners, so my advice is focussed on chemical-free organic control methods.
Apple canker can become a big problem on wet and acidic soils. If this is the soil type in your garden, you will want to avoid some of the most susceptible varieties such as James Grieve, Worcester Pearmain and Cox’s Orange Pippin. I provide some options for apple canker resistant varieties at the end of the video.
⌚ Timestamps
00:00 Should you worry about apple canker?
00:28 Symptoms of apple canker
01:50 What does apple canker do to your tree?
02:23 Wet and acid soil encourages apple canker
03:02 How to cure apple canker
04:53 Canker resistant apple varieties
Lastly: opinions stated in this video are my own. I have not been paid to sponsor or endorse any of the gardening products I mention or use in this video.

[@rebekahtheukplantdoctor]

Have you spotted the tiny red balls caused by the apple canker fungus like you can see at 1:17? These tiny red balls are a clear sign of infection, and a reminder to prune those cankers out! 🌸

[@swilson5260]

Thank you very much for this helpful video. Our apple tree's main trunk is affected.Should we aim to cut out the canker? It runs up and down the trunk like a tear. Several other branches are affected too. Possibly the canker has been there for a few years but we have only just noticed it. The tree has been fruiting beautifully despite this disease. Many thanks

[@rebekahtheukplantdoctor]

Unfortunately cankers on the main trunk of the tree can be tricky to manage. It is likely that the canker will continue to slowly increase in size and weaken the tree. However, cutting out the canker (if it is extensive) would also weaken the tree. Neither option is ideal! If the tree is otherwise fully healthy then it may be sensible to use a ‘watch and wait’ approach. Make a note of the size of the canker now and keep an eye on it. Sometimes the apple tree can form a protective callus to keep the canker in check, in which case the tree may be fine for many more years. But if it starts to expand rapidly then cutting it out would be the best option. Best wishes, Rebekah 💮

[@swilson5260]

Thank you very much for your reply and that all makes good sense. It's kind of you to take the time@@rebekahtheukplantdoctor

[@rebekahtheukplantdoctor]

@@swilson5260 No worries! 🌸

[@Theluvnit07]

The green color on the branches is caused naturally? Or is that also a problem ?

[@rebekahtheukplantdoctor]

Hi there, the green colour on the branches is generally moss, lichen, or algae. This can occur more on dead wood, but healthy trees may have it too. Hope that helps! 🌸

[@DarrenPoole-x1f]

Thank you for this absolutely excellent and very informative video, it is a super clear explanation and excellent images to accompany the explanations. I had 7 apple trees all on M26 stock and from the same specialist fruit nursery all of which turned out to be very stunted trees (about 3.5 feet high) which produced either no fruit or a few very tiny fruit, the rootstock was clear infested, and I had thought it was canker in the rootstock below the graft union, but I now think it more likely to have been apple Phytophthora but still unsure. After 15 years being planted I have now dug them up and replaced with new trees. I’m now concerned about apple replant disease or the phytophthora infected the new trees which are basically in the same place in my small orchard (45 apples plus other top fruit too). So any future video about apple Phytophthora and apple replant disease, identification, effects on the tree and possible remedies, would be really helpful if this is something you may consider. Thank you so much again for this really excellent video, with very best wishes, take care, Darren

[@rebekahtheukplantdoctor]

Thank you Darren, I'm really pleased you found this video helpful. Only 3.5 feet high on a M26 rootstock in 15 years certainly sounds like your apple trees were struggling. Or perhaps there was a chance the supplier mixed up the rootstocks, and supplied with M27 rootstocks? Otherwise, yes, Phytophthora does sound like possible cause of the poor growth. Root problems such as Phytophthora and honey fungus are certainly on my list of future videos to produce, but I have to wait to find the clear examples of the diseases to get the footage. Wishing you sucess with your new apple trees, best wishes Rebekah 💮

[@lamaestro3143]

Thank you for the video! What if there is canker on the tree trunk close to the soil? I hope I don't have to chop my whole tree down!

[@rebekahtheukplantdoctor]

@@lamaestro3143 you’re welcome! Unfortunately canker on the trunk near the base is very hard to treat. If it’s a small shallow canker you may be able to cut out the infected wood but still keep the tree alive. But for a larger canker the tree may not survive any treatment. You’ll need to weigh up risks in your garden. Do you have other apples which are healthy right now? In which case you may want to act to protect them. If it’s your only apple tree then you can watch and wait. Trees can survive a long time with canker, although will decline over time. You also want to monitor the safety/stability of the tree as it declines. Good luck 🌸

[@ahoffman1979]

Thank you so much for this informative video. I discovered a sunken lesion on my Enterprise tree last night and had deduced it is likely canker. The canker is in a large leading branch off the main trunk, so it will be a significant cut, but I know it's needed. Is winter the only appropriate time to cut out the infected wood? I am worried about it spreading to the nearby trees in the coming summer and winter if I leave it. I live in a hot, humid climate (eastern Tennessee, USA).

[@rebekahtheukplantdoctor]

Hello Angela, I’m glad you found the video helpful. The canker can produce spores in summer and winter, so the longer it is in place the higher the chance of infection spreading to other apple trees nearby. However, summer pruning on apples is usually focussed on removing thin leggy growth, and making a significant cut in summer carries more risk for the tree. Having said that, the canker is also damaging the tree. So for me, balancing the risk of the two options, I’d personally go ahead and cut out the canker now. Prune in dry weather and clean your tools before and after each cut. Good luck 🌸

[@ahoffman1979]

@@rebekahtheukplantdoctor Thank you so much for your reply, advice, and encouragement. I'd like to take it out sooner rather than later, too, especially given the risk to our other nearby apple trees that now have fresh cuts on them from summer pruning. We have a stretch of predicted dry days this week, so I'll go out and take care of it tonight. Thank you for providing me with the confidence to do so now!

[@ahoffman1979]

I'm sad to report that the tree is a loss, as the diseased tissue was present going down into the main trunk, even when I stump-cut it at only about 12" tall. I'm glad to know now to take it out, though, lest it infect other nearby trees.

[@rebekahtheukplantdoctor]

@@ahoffman1979 Angela, I’m sorry the tree is a lost cause, it’s always sad to lose a tree. As you say, the good news is that you spotted the canker and have taken the right action to reduce the risk to your other trees. Make sure you take a good look at your other apple trees this winter and prune out any small cankers you spot. Good luck 🌸

[@ahoffman1979]

@@rebekahtheukplantdoctor Thank you again for the advice and encouragement. It was sad to lose the tree, especially so because we only have four apples (now three) and just ventured into them three years back. However, now that I know what to watch for, I hope I'll catch it more quickly if it recurs, and I will check the remaining three for canker in the winter. Best wishes!

[@l0tus4life]

Thank you

[@rebekahtheukplantdoctor]

You're most welcome! 🌸

[@drmichellecook]

Thanks for the great information.

[@rebekahtheukplantdoctor]

I'm happy to have helped! 🌸

[@tomgatum4330]

Thanks for sharing

[@rebekahtheukplantdoctor]

You're welcome Tom! 🌸

[@marktapley7571]

If fungicides are not available in the damp climate of England, you might as well forget about growing apple trees. People need to reclaim their rights to manage their own property as they see fit. Just because you are not a commercial grower you should not be discriminated against by the government that you are paying for.

[@rebekahtheukplantdoctor]

Fungicides are a very nuanced and controversial topic. I know plenty of growers who have healthy apple trees without fungicide use - including myself. But these garden apple trees in the UK also don't have to grow commerical-sized yields. There's a time and place for many plant health solutions! Rebekah 🌸