Did any of your peaches ever get black knot? New plan for dealing with black knot

General Fruit Growing
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Did any of your peaches ever get black knot?

I read apples are immune to black knot. The article said peaches can get it, but are less susceptible than plums.

What do you think about this plan for dealing with black knot?

If you grow plums, apples and peaches. And peaches and apples don’t get black knot. Then just grow plums and disregard the black knot. I had terrible black knot on all my plums, and they still produced fine and were healthy trees otherwise. I cut the plums all down as I was worried my other trees would get infected.

If a tree loses vitality from knot, then cut it down and replace it. All my plums cut down were 13 - 15 years old and showed no sign of problems producing fruit. My trees all had knot for years. I just didn’t know what it was. I thought it was cicada damage.

BTW…Green Gage plum, one of the best eating plums, is highly susceptible to knot. It was the first of my 6 plums to get cut down. Plums are a must to grow around here. All the plums and other stone fruit in the stores are inedible garbage.

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Never had black knot on peaches. Not to say it’s impossible, but I haven’t seen it yet in my location. The wild trees nearby are loaded with it.

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It’s pretty much only plums that get black knot. I may have seen one on an apricot once, not sure though.

I don’t think you want to let it go, it can drastically affect the tree. Our neighbors old plum tree died from it. Just prune them out and blowtorch them, its not that hard.

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What part are you blowtorching?

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The whole area where the bark was scraped off, right up to the bark still there. I make sure it’s all blackened. No need to start a fire though … :grin:

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OK thanks. I would think it would kill the branch from the heat. Or is this only used on big branches.

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Yes, maybe 1" is the smallest it works reliably on. For 1/2-1" branches I sometimes just cut the knot out and then watch it to make sure it’s OK. Or I might give it a light blowtorching treatment, careful to not get it too hot for too long. I’ve never killed a branch with the blowtorch believe it or not. You need to make sure there is one side you are keeping out of the heat, that will be the bark bridge that feeds the rest of the limb.

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Does black knot get down in the roots and first two feet of the trunk of plum trees?

Is there a plum variety that is absolutely immune to black knot?

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I’ve never seen it on the main trunk on my trees. Just off the main trunk I have had some infections though.

I don’t think there are any immune varieties. There are definitely degrees of susceptibility though, lots of posts here about relatively good and bad varieties.

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I know you’ve talked about this a lot, but can you share what kind of knife you use to do this?

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I use a wood carving knife since thats what you are doing. The main thing a good carving knife can do is they have a thicker “V” blade and are less likely to “catch” because of that. I have some old Mora carving knives I use, they should have a big “V” on the blade cut, like this one:

That big wide V can be seen in the picture. You sharpen by putting each V side flat on the stone, so the edge is all one continuous V. Thats needed to get a smooth cut, if you sharpen it wrong you ruin the knife. At least thats my opinion.

That said, I usually use my grafting knife because I’m always carrying that. I get the carving knife out for bigger jobs on knots or cankers.

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