Grafts survived 17 degree freeze?

For the last several years I’ve found I get the best results grafting on apple trees outside by grafting just before or at first growth. At this time in the season we’ve never had temps dip into the teens- until this year.

I had spent almost a full days work doing many grafts on apple trees in my nursery and a few in my orchard when just a couple days after we got down to about 17F.

I thought I’d possibly wasted all those hours of work but the grafts seem to be sprouting out normally. At least a couple others on this forum suggested my grafts would likely be killed. I’m wondering if this first growth indicates I’ve escaped any serious damage- the young shoots look fine.

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That would make sense - the scions being dormant.

If you wrapped them in parafilm, that would have helped with desiccation.

In Bob Purvis article I read that it is the callus tissues that are damaged during the freezing temperatures. I would suggest that if callus tissues are not formed yet, then the scions will not be damaged. Some people used to keep their scions in the snow during the winter, so the light freezing temperature is fine for the most varieties.

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Alan,

We didn’t have 17F spring temps here, but it did get down in the mid 20s after I grafted. I thought the apples I grafted before that were dead. The pears I grafted a little before the apples had sprouted a little bit, but the apples looked dead.

We had such warm a Feb. some apples and pear trees were pushing growth, so I decided to graft. Then we got a solid month of very cold weather. However, in the end just about all the grafts took.

They just seemed to sit there during the cold weather, with no harm (even the pear grafts which had sprouted just sat there). The only problem I had was w/ apples I cleft grafted on larger stumps. None of those took.

I only grafted about 10 apples, and maybe 8 pears, so not a big sample.

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I did that once on pears and had very poor results. So I stopped grafting really early. My guess is the exact way the temps progress is what matters, for example if its warm for two days after grafting it might be all OK. My recollection when I did it was it chilled immediately after I grafted.

This year I had a really long window of perfect high 70s-80s on my peaches, and its looking like I will get a very high percentage of takes. It did cool down but there were five solid days of perfect weather before it cooled.

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Scott, I haven’t found any particular relation to the percentage of takes with apples or pears in terms of follow up warm spells. It may be true of stone-fruit but I think I’ve done this early grafting enough to have a pretty good handle on the effects of subsequent weather. If it held true for apples that cool weather after grafting reduced takes I wouldn’t get near 100% takes from my early grafts onto vigorous trees. Lots of cool weather in the first 2 weeks of spring here.

This year I’m gathering evidence on how much weather temps are involved with peach graft success as I did some a week ago and we are having nothing but wet cold days from a day or 2 later on. I will graft peaches and plums this weekend and warmth is supposed to arrive for a while starting then. I will compare the peach success and let you know.

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Alan, I was referring to the period immediately after grafting, not the next weeks or month. My impression is the first couple days after grafting matter a lot more; the year my pears failed it cooled less than 12 hours after my grafts were done. So, if you grafted early and it was warm two days and then dropped to super cold for a long time it would not surprise me if you still had many takes.

What I’m saying is I’ve done the early grafting for years irregardless of subsequent weather and results have been consistent, even when I grafted in very cool conditions with apples and pears.

The first peaches this year got one day of temps in the low '60’s and then it turned wet and cool in the low 50’s. Would you consider that a test of affects of cooler grafting temps? It is almost always in the mid 60’s or warmer when I graft peaches but this year I got tired of waiting.

Ah, I missed your point somehow. Maybe I will try some early grafts again, I only tried it one year and got nothing but blanks.

Yes those temps sound like a real test of peaches, I had little luck there. Let us know how they turn out. I’m having one of my best peach years, it looks like almost every peach scion is sprouting.