D. kaki death in zone 8 (SDS)

[fruitforestNC8a]

I’ve read many posts about the cold tolerance of various kaki persimmon cultivars here.
My experience with my Asian persimmons made me seek out how their tragic deaths could happen here in zone 8.

In 2020 I planted Giant Fuyu, Saijo and Fuyu.
They grew and in 2023 my Fuyu had 9 fruits.

Encouraged by that I ordered a Giombo and a Hachiya, planted in 2023.

This past Spring of 2024 I knew something was wrong when all of them were only sprouting at the base below the graft.

I removed those rootstock sprouts to force the graft tops to sprout. None sprouted, the bark scratch test showed they all had died.

So I then let the D. virginiana rootstocks grow so I can graft onto them later.

I asked the county extension agent what could have caused ALL of the previously healthy trees to die ?

Their answer was D. kaki has ( I’m paraphrasing) a low chill hour need, about 200 hours or so.
Shortening day length triggers their dormancy and they reach peak dormancy and can take the cold.

But once that chilling requirement is met the tree begins to de- acclimate and becomes more sensitive to cold again.

Very likely to be bud damaged if the chill hours were met by the end of December in my case.
He told me in January and February of 2024 there were 18 nights of below 30 degrees F.

I guess the killing of the entire kaki grafts then happened around the night of January 20 when the
Low temperature was 18 degrees F.

Personally I think that after the chill hours required have been met the trees are in danger when the weather heats up temporarily for several days, even weeks, and winter is definitely not over !

So I have a strategy this winter for my kaki grafts that I made onto my wild persimmons this Spring 2024.
At the beginning of January 2025, once my Chocolate, Coffee Cake and Fujiwara Gosho grafts are dormant I will cut scionwood from them as an insurance to be regrafted in Spring 2025.

Also I will use insulation foam (for pipes) on the kaki branch that remains on the tree. I will cover the black foam with aluminum foil to try to prevent it heating up in the sun.

I welcome a better solution to my NC erratic winter weather for my persimmons if you have one.
Thanks for reading this, it was long . Smile

[Fusion_power]

Is “kiko” deliberate? or spelling? Otherwise, consider grafting some of the hybrid persimmons like Dar Sofiyivky.

[fruitforestNC8a]

It could be my spell check
. I’m writing about my Asian persimmons, D. kaki.
Sorry for the confusion.

[evilpaul]

Just put some shade cloth over the Kaki plants/grafts? Or use a tree wrap until they get older/larger?

[fruitforestNC8a]

I actually did put some agricultural frost blankets on the small Giombo and Hachiya but they died.
All of them were marketed as fine for zone 8a.
So I was quite surprised when they died.

[fruitforestNC8a]

Are you growing the Dar Sofiyivki ?
I just looked it up, it sounds great.
I will definitely add that to my wishlist for next winter.

I have already a lot of scionwood ordered for this year.
I did order the hybrid Nikita’s Gift.
Also I will be grafting Dollywood, Mohler, Early Jewell, H63-A, Great Wall, and Giombo.

Also apples, pear, cherry.

[Fusion_power]

Yes I have Dar Sofiyivky courtesy of a tree from Dax. I will offer scionwood sometime in January. I just added a note you would like a stick.

[Gkight]

I completely disagree with the ag agent. I think more likely this was delayed graft failure rather than too many chill hours. Also could have been drought which dried out the graft but the rootstocks survived. A lot of things could have went wrong all much more likely to me than too cold in zone 8. Do you have any photos of them as you planted them? Perhaps too deep planted and wet feet, perhaps too dry. Were they small whips when you planted them and how much did they leaf out where they didn’t leaf back out the next spring.

[jrd51]

@Gkight

I completely disagree with the ag agent.

I’m with @Gknight. My three Ichi Ki Kei Jiros, planted in 2015, suffered some damage the first two winters but after that they survived with only minor tip damage (new growth) into 2023. That’s despite frequent occasions when nighttime temps dropped to 0 to -3 F in Dec/Jan/Feb and many others when temps dropped to 20 to 30 F in April or even early May. As far as I can see, the trees stay deeply dormant until temperatures have been consistent warm (e.g., 50-60 F) for a spell.

The only time the trees were damaged was in a severe cold spell in Feb 2023, when nighttime temperatures dropped to -5 and -7 F. In this instance, all 1-2 year old wood was killed but the older wood eventually sprouted and the trees all regrew.

My takeaway is that these trees are hardy to approximately -5 F. Other Kaki varieties may be less hardy, but I feel confident that they would tolerate winter temperatures down to +5 - +10 F without any problem. A late spring frost (+20 - +30 F) might do severe damage but only after a period of sustained warm temps that initiated growth.

I suspect your trees had other issues.

[ncdabbler]

I concur with @jrd51 and @Gkight that I doubt it was cold damage that killed your trees. I’ve been growing kakis in central NC for over a decade, and they seem to handle our wild winter temperature swings and early and late frosts much better than most other types of fruit trees. I have had minor dieback from late frosts, but I’ve never had any trees die during the winter like you’ve described. I’ve had winter lows close to 0 deg F and lots of warm stretches mid winter followed by an abrupt drop back down below freezing. This has wreaked havoc on my other fruit trees that aren’t well adapted to our NC climate and break dormancy too easily (especially figs and pomegranates). But my kakis have stayed dormant through those same conditions. I’ve lost many kakis to sudden death syndrome as you’ve probably read about on the forum, but that usually hits them in the late spring or early summer after they’ve put out an initial flush of growth. I’ve had a couple trees that were damaged by bark splitting at the base of the tree - and that could be due to the temperature swings in the winter. Initially, I painted all the trunks with diluted interior latex paint, and that may have helped. I should probably do that again. Insulation foam and aluminum foil probably wouldn’t hurt anything but in my experience wouldn’t be necessary to protect recent kaki grafts. Some nurseries, especially those on the west coast, graft D. kaki onto D. kaki or D. lotus rootstocks instead of D. virginiana. I’ve never grown anything on D. kaki or D. lotus rootstocks here in NC, but they’re supposed to be more susceptible to diseases and less tolerant of poorly draining clay soils like mine here in the Piedmont. I would be more worried about young kaki trees drying out or getting too wet during the winter, and that being the reason they died. Perhaps the trees were stressed and that caused the graft failure, but the tough native D. virginiana rootstocks were able to survive and regrow, as @Gkight was describing. I like to plant my fruit trees on mounds about a foot above ground level to avoid some of the drainage issues for young trees in my poor soil.

[fruitforestNC8a]

Oh thank you ! That’s very kind of you. I have wild persimmon trees waiting .

[GrapeNut]

I remember reading somewhere that persimmons need a certain amount of heat accumulation to break dormancy on top of their chilling requirement. So loss of cold acclimation during the winter seems unlikely unless you have a string of very warm days. Where I live in California, we reach 200 chilling hours by the middle-end of November, yet persimmons are among the last trees to break dormancy in spring.

[fruitforestNC8a]

My thanks to each of you for your detailed descriptions of the weather that your kakis have survived over the years.

I will try to post photos of how Fuyu and Saijo looked in summer of 2023.

The soil in my orchard has no clay or rocks. It is sandy. There is no chance of them being in standing water.
I have every tree surrounded with wood mulch. I put a few nightcrawler worms with each tree to break down the mulch faster into better soil.

I can reach every tree with the water hose and keep them moist enough. I water less while they are dormant.
My orchard includes persimmons, apples, pears , stone fruit, figs, blackberries, blueberries, etc.
All seem to be doing well.

The rootstocks of the failed kaki have grown well enough this year that I may be able to graft onto them next May 2025.

I don’t think I planted too deep.
When I post the photos I will give specific info.

[disc4tw]

I recommend searching the forum for kaki SDS and also if you don’t think this is a disease related challenge, graft to hybrids known to leaf out late.

[fruitforestNC8a]

Saijo planted 2020, photo taken 2023.

[jrd51]

I lost a purchased tree to sudden death syndrome this past summer Right now that sounds your most likely explanation.

[fruitforestNC8a]

Fuyu planted 2020. Photo taken summer 2023.

[fruitforestNC8a]

The Giombo and Hachiya were both planted Fall of 2023. They went dormant and never woke up in Spring of 2024.
Giombo was from JustFruitsandExotics. Hachiya was from OneGreenWorld.

[fruitforestNC8a]

Hachiya

[fruitforestNC8a]

The 5 rootstocks seem to not all be behaving identically. Some went dormant already and others are slower to lose leaves. Photo taken November 17, 2024.