My apples will be OK.
I was wondering about that or possibly sterno cans. Not sure they would put enough heat out though.
So new blueberries -do they come inside? I was planning on the kiwi, was leaving blackberry. Or I can take them all in over the weekend. I have put almost everything in pots until I have soil leveled and tilled.
I think if I had just a few trees for home use, I’d consider just getting a smudge pot (if you think it would be permissible in your city. They do have a flame coming out the top. I’d imagine if the city doesn’t complain about tiki torches, they wouldn’t complain about a smudge pot, but who knows.
They are kind of expensive.
Here is one on ebay for $200 including shipping. But it wouldn’t come in time for this freeze event.
They burn with diesel fuel, or used motor oil (though they would smoke a lot with motor oil). Kerosene would obviously burn the cleanest.
They are designed for the purpose of protecting fruit tree crops. My understanding is they work pretty good. I’ve forgotten the amount of area they cover, but that info is available online.
Another option might be to surround the tree with some swedish logs, if you have access to wood. The burn time is supposed to be about 3 hours, so you’d likely have to light a couple different sets to protect from the coldest part of the night and morning.
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Latest is calling for 30 here … if that is correct, no problems here in Kentucky. (Maybe for stone fruit, but I don’t have any of that).
Thinking the same thing. Once upon a time orchards were protected with oilpots that looked like cannonballs. Another method , perhaps still used, was very large fans to keep the air moving and pick up some warmth from the ground.
I’ve also heard of people filling food grade plastic barrels with warm water and putting it at the base of tree for a night or two.
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What’s the projected wind like?
i think the sprinklers might be a viable way to go.
it takes the same amount of (heat) energy to cool water from 176F to 32F as it takes water at 32F to go to ice at 32F.
You don’t have to continuously spray. You just need to make sure there is enough water to freeze around. So as soon as stuff is no longer “wet” but just coated in ice, you need to water again.
If you have a timer you could let the sprinklers run a few minutes every 15 minutes or so.
you do need to make sure the sprinklers hit the blossom. Having the ground wet but not the blossoms does little for you.
This has also been discussed in this topic.
i think the fans where used to get warmer (non freezing) air, from higher up. Not to pick up warmth from the ground.
And that only works well when there’s a radiative freeze and it’s relatively wind free.
Sunday night is supposed to be windy as hell, but “only” 28 so that is probably doable. The really cold night, I think, Monday night, should be more still and down to about 22. I have a timer but it is just the wind-up type (set for X minutes and it shuts off, it’s not electronic).
although i agree with your advise. The water melting, does not make the plants colder. It just slows down the plant heating up.
Think about it. If the ice is melting, the ice (and thus plant) are at or around 32F. If ice melting would lower the temperature, it would freeze water again, and you’d get into a weird physics defying loop.
The real danger is when the ice/plant are no longer wet, and ice starts to sublimate (go directly from solid to gas). That actually cools down the ice. (and plant)
Having 1 kg (or gallon) of ice sublimate into gas, absorbs the same amount of heat energy as roughly 8.5 kg (or gallons) of water freezing “releases”. Luckily sublimation of water usually happens only a little. And as long as there is water around to released the needed (heat) energy. It won’t matter much.
there is still time to source an electronic timer…
Do select one that is rated for your (inductive?) load.
is Monday night a clear sky? (no cloud cover) i suspect it is. That would be a typical radiative freeze. And luckily is a lot easier to deal with than a convective freeze.
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You are exactly right. I got confused on that detail. It is important to not to stop irrigating too soon though. I’ve read that in many publications.
Here is one which says not to stop irrigating until the wet bulb temp is 34F. As you know the dry bulb (“real”) temp would be a few degrees higher under low humidity conditions, which really means one wouldn’t stop irrigating at least till the “real” dry bulb temp was at least 34F.
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You need to read this: Using sprinklers to protect plants from spring freezes - MSU Extension
THe advice you are giving is not true
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Credit to @clarkinks, who posted this link in the past: Picture Table of Critical Spring Temperatures for Tree Fruit Bud Development Stages - Fruit & Nuts (msu.edu)
From which I got this chart:
So, for me at least, it looks like I’ll get somewhere more than 10% kill, but less than 90% kill. Honestly, there are so many blossoms that even if I get around 50% kill, that’s still more than enough for me and my family off of my few small trees. So, I can live with that!
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i have read that link.
Could you specify what advise if given that is untrue in your opinion? And if possible also argue why it’s untrue? (or tell me what is true?)
You have to keep the ice continuously wet. If the ice dries off then it’s getting colder. The ice needs to be wet because it’s the freezing of more water into ice that’s holding the temperature at 32F. As soon as the ice dries it’s dropping below 32F.
Also shutting off the sprinklers is going to result in frozen lines and nozzles. Once frozen they may not unfreeze when the water comes back on.
This is specifically addressed in that article.
Officially supposed to be 27 here Sat night (which means it could be 22-32), so my trees ought to be okay, except for my pluots, which are already blooming to some degree.
Ohio crap We are now going down to 22F. My figs and citrus tress will need to come inside. If my cherries an Blueberries loose the flowers to cold they should put on really good growth. My Turnbull giant pears are.
fortunately the Turnbull giant flowers twice. Pictured above is on Callery roots.
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i don’t see where what you typed differs from what i said before. IE, what did i say that was untrue?
Your point of the sprinklers freezing shut is a valid one though. And something to look out for. I once talked to a grower who had his overhead frost irrigation on an on/off timer. He didn’t seem to have problems with the irrigation freezing shut.
But thinking back we didn’t discus timings. So maybe 15 minutes between is a little bit dangerous.
Water doesn’t freeze instantly though.
And a home irrigation system is more likely to be oversized compared to an industrial one.(especially if used for just 1 tree)