Author Topic: Citrus damage after freeze  (Read 3941 times)

Perplexed

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Citrus damage after freeze
« on: December 23, 2022, 12:59:23 PM »
There is currently an ongoing hard freeze happening now and probably the weekend. I would like to hear any data of frost hardiness of any citrus varieties following the event. It's going to get doen to 10 degrees F here, so I'll record my data and not protect anything.

Unicyclemike

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Re: Citrus damage after freeze
« Reply #1 on: December 24, 2022, 03:25:23 PM »
I can't wait to hear your results.

Mike A.

Perplexed

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Re: Citrus damage after freeze
« Reply #2 on: December 24, 2022, 07:42:36 PM »
Went down to 9. I’ll figure out what is damaged or not probably after a few days since we’re still below freezing for over 24 hours.

vnomonee

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Re: Citrus damage after freeze
« Reply #3 on: December 24, 2022, 07:59:05 PM »
Following, and I'll report on these in a few days, low of 5f: *small update*

Yuzu on own roots somewhat protected (stacked bricks covering the main stems)- this one died to the ground last year at 6f with freezing rain- lots of damage on the top of leaves and tender growth turned white and burned

Yuzu on Poncirus -damaged leaves

Tai-tri own roots- leaves turning yellow no obvious damage to stems

Citrumelo own roots- leaves curling no obvious damage to stems

Morton on Tai-tri- scion looks a little dry

Morton on Citrumelo- scion looks a little dry

Prague on Tai-tri- whole branch turned slightly yellow (is this poncirus influence?) leaves turned yellow

Prague on Poncirus- top looks sun burned but lower part of plant is fine with green leaves

Ninkat x Poncirus- top looks sun burned but lower part of plant still holding leaves

random seedlings of kumquat and sour orange- some survivors of kumquat, sour orange very damaged, random yuzu seedling took almost no damage just top leaves

and of course Poncirus/+ which shouldn't have a problem- still holding leaves

Non-citrus:
Feijoa protected (agribon + incandescent lights)- healthy green color leaves look good, small amount of leaves closer to the top of the fabric slightly dry and light brown possible damaged from touching fabric

Feijoa unprotected - these dropped leaves  last year at 6f with freezing rain- light brown leaves definitely damaged not as bad as last year

Kadsura coccinea somewhat protected (stacked bricks and agribon small plant not a vine yet)- two tender young leaves turned brown at the top otherwise the whole seedling survived

Loquat small graft on apple- doesnt appear damaged
« Last Edit: December 29, 2022, 02:22:18 AM by vnomonee »

Perplexed

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Re: Citrus damage after freeze
« Reply #4 on: December 24, 2022, 09:11:47 PM »
I’ll report on these on Monday, should be above freezing on Monday and should be straight.

5* star citrumelo - Grafted
Dunstan citrumelo - own
Taitri - own
Ichang Papeda - Grafted
Dimicelli - Grafted
Ventura Lemandarin - own
Citrangremo -Grafted
F2 Cirus glauca/finger lime? - own
F2 Citrus australis - own
N1Tri x Citrus - own
Ichangstar60 x Citrus - own
Citrus hongheensis x Citrus - own
Razzlequat - own
Citrus taiwanica - own
Citrus glauca x shek - grafted
All grafted are on poncirus

I also have ornamental trees like Cinnamomum, and Persea I may report on.

« Last Edit: December 24, 2022, 09:21:08 PM by Perplexed »

tedburn

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Re: Citrus damage after freeze
« Reply #5 on: December 25, 2022, 09:31:32 AM »
@vnomonee and perplaxed, very interested in your results, though some damages are not seen now but only in april/ may. We had freeze in winter 2020/21 down to 3,6 F and after freeze I thought plants to be still green and don' t hit by freeze, but then they died until april/may.
We had a few days freeze in December down to 8,6 F (unusual for december) but up to now only a few new branches a little bit hurt, nearly no damages.

vnomonee

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Re: Citrus damage after freeze
« Reply #6 on: December 29, 2022, 01:36:44 AM »
Good point about plants later dying in the spring, that actually happened to my 4ft tall yuzu that ended up dying all the way to the ground in the spring. Had a look at some of the stuff today, I think the sunshine damaged the hardy plants more than the actual cold... am seeing what looks like sun burn/scald. Winter is far from over so there might be colder days. Hopefully not! 

« Last Edit: December 29, 2022, 01:46:25 AM by vnomonee »

Citradia

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Re: Citrus damage after freeze
« Reply #7 on: December 29, 2022, 08:39:52 AM »
I had a five-foot-tall citradia die one spring after it put out two inches of new growth after last freeze and noticed that the trunk split on south side of tree. I think it was a zero-degree winter that year.

Perplexed

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Re: Citrus damage after freeze
« Reply #8 on: December 29, 2022, 12:52:57 PM »
Not looking too good right now, but I’ll report later when things warm up after a while.

Millet

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Re: Citrus damage after freeze
« Reply #9 on: December 29, 2022, 02:10:47 PM »
It will be several months before you know he extent of damage.

tedburn

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Re: Citrus damage after freeze
« Reply #10 on: December 29, 2022, 02:48:32 PM »
I’ll report on these on Monday, should be above freezing on Monday and should be straight.

It also would be interesting, how d the grafted plants are and how long they have been planted in ground - thanks

5* star citrumelo - Grafted
Dunstan citrumelo - own
Taitri - own
Ichang Papeda - Grafted
Dimicelli - Grafted
Ventura Lemandarin - own
Citrangremo -Grafted
F2 Cirus glauca/finger lime? - own
F2 Citrus australis - own
N1Tri x Citrus - own
Ichangstar60 x Citrus - own
Citrus hongheensis x Citrus - own
Razzlequat - own
Citrus taiwanica - own
Citrus glauca x shek - grafted
All grafted are on poncirus

I also have ornamental trees like Cinnamomum, and Persea I may report on.

Unicyclemike

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Re: Citrus damage after freeze
« Reply #11 on: December 29, 2022, 06:11:05 PM »
My question is this.....How much time does it take from formation of flower bud to the actual picking of the fruit? Do they need as much time as apples.....ie May flowers bloom.... to Sept./Oct when the fruit is usually ripened....

poncirsguy

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Re: Citrus damage after freeze
« Reply #12 on: December 29, 2022, 10:44:10 PM »
April flowers ='s  December fruit.

vnomonee

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Re: Citrus damage after freeze
« Reply #13 on: December 29, 2022, 11:03:36 PM »
Depends on the citrus. Some ripen their fruit by fall. Others over the winter or into spring which won't work for me outdoors. I'm only collecting hardy varities that can ripen by the fall, with some exceptions I'm not sure when ninkat x poncirus ripens and pretty sure Yuzu won't color up until December which is too late but then again some citrus can be used before they are ripe. they will be sour, so can be used like a lemon. I don't plan to eat anything hardy I grow fresh off the tree will have to be processed in some way.   

My question is this.....How much time does it take from formation of flower bud to the actual picking of the fruit? Do they need as much time as apples.....ie May flowers bloom.... to Sept./Oct when the fruit is usually ripened....

Citradia

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Re: Citrus damage after freeze
« Reply #14 on: January 02, 2023, 09:00:25 PM »
I was having lows in single digits two days in a row with a known low of 2 degrees F, and not above freezing day and night from Friday through sometime the following Tuesday last week. I also lost power for two hours and couldn’t get generator started Friday morning as temperatures plunged to 8 degrees with a high that day of 11 degrees. All of my store-quality citrus have massive leaf damage but no trunk splits noted yet. Most of my Citradia trees, Dunstan, 80-5, Thomasville, Benton citrange that are unprotected only showing mild to moderate leaf damage. One large citradia on east side of an unheated cold frame with yuzu in it actually looks unscathed for now. The yuzu in unheated frame looks remarkably good with some leaf damage only.

I had to cut back on my use of space heaters due to inadequate amount of electricity to support my 15 outdoor trees in cold frames covered in 4 mil plastic sheeting. Each frame has potted citrus seedlings and grafted trees also. The poncirus hybrids even the newly grafted potted ones are unscathed.

My winners for this event so far with only one 250 watt space heater inside each enclosure are:
Saint Anne Satsuma ; only a few burnt leaves.

Seedless Changsha on flying dragon; few burnt leaves only.

Meiwa kumquat ; no leaf damage but lost all fruit.

Trees with moderate leaf damage in frames:
Croxton
Owari
Kimbrough
Seville sour orange : all fruit lost
Bergamot
Yuzu: unheated frame w 50 gallon water barrel

Trees with severe leaf loss:
Rio Red grapefruit : fruit lost
Changsha : unprotected
Shiranui
Sugar Belle
Ichang lemon

All frames have at least one water barrel and all at least one 250 watt space heater w larger frames having two heaters and two or three barrels.
I’m having another electric outlet installed outside by electrician next Monday.


tedburn

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Re: Citrus damage after freeze
« Reply #15 on: January 03, 2023, 03:42:36 AM »
interesting post, big job 😉.
Could you also measure the deepest temperatures which the different citrus has to support, this would be interesting to judge the frosthardiness which the digferent cultivars did take. I understand that the 2° F have been outside and not in the tunnels ?

Citradia

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Re: Citrus damage after freeze
« Reply #16 on: January 03, 2023, 07:34:07 AM »
Yes, the 2 degrees F was outside temperature. I have used a digital thermometer about 6 years ago and noticed that the Rio Red got down to 19 degrees inside tent with heater on when it was zero degrees outside. The tree survived with minimal leaf damage. During that polar vortex, the outside temperature dropped a degree every minute as soon as sun went down, and dropped a degree every few seconds inside tent when heater turned off. This proved to me that I have to have heaters and cover citrus to keep them alive here.

tedburn

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Re: Citrus damage after freeze
« Reply #17 on: January 03, 2023, 02:04:18 PM »
thanks, very interesting. I planted some 2 year old seedlings of Star ruby Grapefruit in front of my Glasshouse and protected them with air bubble fleece. I had inside the protection -8° C while outside we had - 13° after a few days with freeze and the seedlings had nearly no damage, so I was astonished how much they can take - and corresponds to your results with your Rio Reds.

Citradia

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Re: Citrus damage after freeze
« Reply #18 on: January 03, 2023, 08:23:15 PM »
Another problem I am facing is that since my trees have grown bigger over the past ten years, I’ve made my cold frames larger, so now I have more air space to heat inside the enclosures, which means adding heaters. I’ve added more water barrels, but it becomes a volumetric math problem to figure how much supplemental heating I need for the size of the enclosure. I think the size of the tree itself is a factor also since it also takes up air space and it’s canopy helps hold heat under it. I also have fewer potted seedlings inside my enclosures this year also. The watered pots also add a passive heating effect and reduce the amount of air volume my small heater has to heat up.

Millet

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Re: Citrus damage after freeze
« Reply #19 on: January 04, 2023, 04:36:21 PM »
You could always use the 4 X 8 silver sided sheets of polyurethane on three of the sides of your enclosures instead of plastic sheets..  These are sold at Home Depot.

Citradia

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Re: Citrus damage after freeze
« Reply #20 on: January 04, 2023, 09:44:03 PM »
Thanks, Millet.

hardyvermont

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Re: Citrus damage after freeze
« Reply #21 on: January 04, 2023, 10:06:27 PM »
8 F, 13 C was not cold enough to differentiate a lot between most hardy citrus.  Both types of 10 Degree Tangerine appear to be more sensitive to the cold than expected, leaves curled more than most.  Brown Select, Changsha, Keraji appear to have done well.  Sugar Belle will probably lose its leaves, but seems to have survived. 

Oolie

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Re: Citrus damage after freeze
« Reply #22 on: January 05, 2023, 12:04:21 AM »
I wasn't in Alabama for it, but the day before Christmas was a low of 16 and a high of 30 https://www.timeanddate.com/weather/@z-us-36360/historic?month=12&year=2022. All first year unprotected citrus defoliated, and many branches died. I may be looking at a few trees that are now rootstocks.

Either way, I suspect Keraji will rebound, as well as Meyer lemon, but 88-2, and Shiranui look pretty poor, and I don't think the limequat will return either. Loquat lost tender new growth and is flushing again. Butias have no damage. Feijoas are perfect.

tedburn

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Re: Citrus damage after freeze
« Reply #23 on: January 05, 2023, 01:59:11 AM »
8 F, 13 C was not cold enough to differentiate a lot between most hardy citrus.  Both types of 10 Degree Tangerine appear to be more sensitive to the cold than expected, leaves curled more than most.  Brown Select, Changsha, Keraji appear to have done well.  Sugar Belle will probably lose its leaves, but seems to have survived.
Interesting information, we also went down to 8° F in December and also have nearly no or no damage, but most of my trees have been fleece protected except Ivia and HRS899. Did you have your trees unprotected and how old are they. Interesting especially for Keraji and ten degree - thanks.

hardyvermont

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Re: Citrus damage after freeze
« Reply #24 on: January 05, 2023, 03:43:40 AM »
Did you have your trees unprotected and how old are they. Interesting especially for Keraji and ten degree -

Trees were unprotected.  They are about 4-5 years in ground, 1 to 4 meters tall.  Shaded leaves looked best.