trees that suffer injury below 45F / 7C?

[brian]

Can anyone think of any fruit trees discussed here that could be injured from brief exposure to temps 40-45F (4.5-7.2C)?

I am starting to bring my most cold sensitive plants into the greenhouse as lows are now in the 40s.

I'm aware of mangosteen and cherapu, durian, plus the various soapberries that are known to be completely intolerant of cold.  I believe the other garcinias commonly available are fine until 30s.   Any artocarpus this sensitive?  Syzgiums?  Pouterias?

The only thing questionable I could think of that I actually have outside right now is spanish lime and malay apple, which I just brought in.  The "ultra tropicals" I have never leave the greenhouse. 

Edit- cacao too

[Jaboticaba45]

Breadfruit and most artocarpus, many Asian garcinias excluding dulcis and a few others.
Cacao and their relatives don't like it either.
Now injury we talking is like a set back or something, short times in that temp range wouldn't kill them. Extended temps do.
Pouterias are fine as well as syzygiums.
How low does your greenhouse get? I was surprised you had marang and others doing pretty well.

[brian]

Thank you.  The only artocarpus I have outside are jackfruit which I know can handle some cold.  My greenhouse heater is set to 55F which should be good enough for anything, I hope.  Marang is doing great in there and has already survived one winter. 

Everything goes in the greenhouse soon enough, I am just trying to do it slowly over the next month.

[Jaboticaba45]

Thank you.  The only artocarpus I have outside are jackfruit which I know can handle some cold.  My greenhouse heater is set to 55F which should be good enough for anything, I hope.  Marang is doing great in there and has already survived one winter. 

Everything goes in the greenhouse soon enough, I am just trying to do it slowly over the next month.

Ok, yeah 50+ is good for basically everything. Could do ultra tropicals although longer times of cold may stunt growth. But glad to see yours doing well.

[nullzero]

I have found Cacao, Abiu, and Rambutan all pretty sensitive to 40s.

[W.]

You might want to go ahead and bring in your Spanish lime, since, based on one of your other posts, it is struggling slightly already (as soapberries are wont to do). I can't definitively remember whether any of mine have been left out for nights in the 40s. Perhaps once or twice, but I want to get as much winter growth out of my plants as possible, so I try and move all my plants in before they get temperatures below 50. I don't always succeed, though.

If Malay apple is like rose apple, 40s should be fine. But, Syzygium is a huge genus, and one probably shouldn't place complete faith that because one plant in it is somewhat cold tolerant, they all share a similar level of cold tolerance.

[nullzero]

Malay apple is more sensitive then rose apple. I had a container 3 year old Malay apple it slowed down and struggled with 40s and died by the end of winter. It never got colder then 40F really that winter.

Rose apple seedling no issues. Pouteria family Lucuma and Ross sapote no issues but Abiu dies in low 40s.

[brian]

Thanks guys.  I have brought the abiu and spanish lime in. 

For fun I left an excess malay apple seedling out to see when it dies, but my large one in the greenhouse

[elouicious]

Mamoncillo will be damaged-

seeds sourced from Jibril, FHC or any of our other central african seed suppliers are also of concern

i.e. Dennetia tripelata all died at 45F for me

[brian]

Thanks.  I don't think I am growing anything African aside from Miracle Berry which I brought in.  I haven't ordered anything from those guys as I don't know much about which of the African fruits may be good to eat

[CeeJey]

RE autocarpus, anyone have experience knowing how more established kwai muk (Artocarpus hypargyraeus) do in the 40s? Mine had some leaf damage and I had to pull them inside last year in the low-40s but they were very small, I'm trying to decide if I should try planting some out near the brick wall this year, or letting them stay in pots another year to get some mass.

I'm actively working on trying to get colder-hardy mamoncillo; I had two mamoncillo out of fifteen or so last year that survived with only a little leaf damage all mesa winter with brief drops into the low 40s, but they were all on a stone patio and got the radiant heat from underneath. Y'all northern folk need to bring back fruit walls: https://99percentinvisible.org/article/fruit-walls-before-greenhouses-walled-gardens-created-urban-micro-climates/

[Jaboticaba45]

RE autocarpus, anyone have experience knowing how more established kwai muk (Artocarpus hypargyraeus) do in the 40s? Mine had some leaf damage and I had to pull them inside last year in the low-40s but they were very small, I'm trying to decide if I should try planting some out near the brick wall this year, or letting them stay in pots another year to get some mass.

I'm actively working on trying to get colder-hardy mamoncillo; I had two mamoncillo out of fifteen or so last year that survived with only a little leaf damage all mesa winter with brief drops into the low 40s, but they were all on a stone patio and got the radiant heat from underneath. Y'all northern folk need to bring back fruit walls: https://99percentinvisible.org/article/fruit-walls-before-greenhouses-walled-gardens-created-urban-micro-climates/

Kwai muk is one of the artocarpus that can take lower temps and even freezes and still come back.
The ones from China are pretty hardy like nanchuansis (like a kwai muk)and gonshanensis.

[brian]

I have a 1/2gal kwai muk I left out, seems to be doing fine in the 40s

[HibachiDrama]

Durian, maybe Abiu, maybe Rambutan, maybe Soursop.

Here is a list of stuff I had in the ground that withstood last year's 3-day freeze at Christmas in NE FL (with varying amounts of damage): several jackfruit, a kwai muk, Ross sapote, Green Sapote, several Garcinia, rose apple.

I had a 3' Spanish lime in my carport and it took no dmg, but all 3 potted Abiu died.

[foresight]

I doubt many people bother zone-pushing Couroupita guianensis, but it definitely doesn't like prolonged exposure in the low 40s, especially if it gets wet feet. My seedlings handled the coldest part of winter just fine (34-35 lows on occasion) with mostly dry soil, but the rains and consistent night temps in the 40s during February and March eventually caused 3 out of 4 to succumb to rot (I brought the survivor inside after the others died). Maybe they could've made it if they were older and had woody stems. Other plants that died in the same period were a chempedak hybrid and a young peanut butter fruit.

[brian]

...Other plants that died in the same period were a chempedak hybrid and a young peanut butter fruit.

Hah maybe I can use this to finally figure out which of my jackfruit trees that lost their label is the Cheena (chempedak x jackfruit hybrid).  The one that dies is it! 

I still have my 20gal peanut butter fruit tree outside in the 40s.  It seems to be okay so far.  That is one for the next round for when we break into the 30s.

I have some "test plants" that I don't care so much about that I can use to judge how cold it really got outside as the weather reports are not very reliable.  A tomato volunteer growing in the mulch pile, a starfruit seedling-rootstock whose scion had long died, and some excess seedlings that aren't worth the effort to try selling. 

[SunshineState]

My 2 year old grafted Spanish lime from Lara Farms took our low of 36 degrees on Christmas for an hour or two with no issues.

[brian]

My 2 year old grafted Spanish lime from Lara Farms took our low of 36 degrees on Christmas for an hour or two with no issues.

That is impressive.  This is the same one I have.  I have read that spanish lime is supposed to be as cold sensitive as mongosteen, rambutan, etc.  But maybe this is not so?  Or at least, it can handle lower temps briefly even if not sustained.

[Fruit Jungle]

I have mamoncillo, chenna, sri gudang, nam cem in the ground that took 40 without leaf damage or set back. They are growing in the best soil, get irrigation, routine manure applications, etc... Meanwhile bilimbi froze to the ground, but wasn't getting irrigated. It eventually came back.

Species in pots did generally worse. Severe leaf damage but had some % survival rate: Theobromo bicolor 50%, cacao, coloc 80%, marang 50%,  cambuca, malay apple. I had no issues with any of the 15-20 abiu seedlings in pots. Species that had 100% death rate: Theobromo grandiflorum, artocarpus sericarpus

There is something to be said about cultural practices. One of the big reasons I decided to grow in a way that maximizes soil fungal populations are the studies documenting mycorrhizal fungi associations and cold tolerance benefits.