Spraying dormant oil before a freeze?

General Fruit Growing
1

Is there really a problem with spraying oil before a freeze?

My plum buds look like they’re about to burst open and I haven’t sprayed them with anything yet. My only opportunity to spray in the next week is today, and I was intending to spray them with copper and oil, but the temps are supposed to get down to the mid 20s tonight. By next weekend (my next chance to spray), I’m guessing they will have flowered.

I never understood the freeze warning with spraying before, but I was mostly looking at fully dormant trees. Will sprayed oil that freezes do any harm to my buds that are about to burst?

Thanks!

2

It can crack/fissure the bark. There within is the problem.

Dax

1 Like
3

Thanks Dax!

So are you saying the buds will be fine, but the bark may suffer?

4

Yes. You are welcome.

Dax

5

Here’s a good link. A very quick read:
Aggie Horticulture: Dormant Oil Archives

Dax

6

Thanks again Dax!

It’s funny, they say the benefits of spraying far outweigh the risks, but also to do it when it’s above 50 degrees and it will be for a few days. The weather for the next few days won’t allow me to do that.

Maybe I’ll just spray with copper and see if the buds are still closed next weekend and spray then if I can? But to be quite honest, I’m not sure I have any problems that the oil will prevent!!

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7

I myself don’t use oil in the spring, but I use a pinene as a sticker it is from the pine tree, like pine tar, this stuff makes the copper stick forever, even after multiple rains.
I don’t know about applying it in freezing weather? I applied mine last week, and may again in a few weeks, if still dormant. I’m in a colder zone probably than you.
I myself prefer to use this with copper, oil does last, and helps with overwintering insect eggs, but the sticker Nu Film 17 with pinene in my opinion will hold the copper to the tree a lot longer. And we are mostly spraying for fungi anyway.

1 Like
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@Drew51 interesting that pine product.

@Bart Just spray the copper and do any insect spraying as necessary with summer oil or whatever you choose.

Have a good one!

Dax

9

Hey Ladies & Gents. I’m doing a combo of dormant oil/copper fungecide all bonide (all i can find locally).

I understand the issues discussed above, I just want to be timely with my spray to make sure I stay ahead of stuff.

All of my trees right now are between silver tip and slighly before half inch green. (Apple, Pear, Peach).

Here is my current weather forecast. weather

My weather is 50s and above from Sunday on and night time temps are 35 or greater for the remainder. If I wait and spray Sunday during the day I should be good correct?

Other question beyond blooming or full on leaves that I don’t expect to see by Sunday, I shouldn’t hesitate to spray, right?