All Things Cold Hardy Citrus, news, thoughts and evaluations


To clarify, I was referring to warm climate citrus I.e. limes, Washington navel, etc.


Most citrus is zone 9 and higher and will not grow in most of zones 5 to 8. There is the orange tree in Birmingham Alabama that is producing fruit. and there are a few varieties of citrus that can take temps down to the teens. Birmingham is definitely zone 7.


Those thorns!


indeed, I dont know if its true but its has been said Trifoliate Orange is used as a Hedge row around the NSA.


Yeah at my parents home in 8b Louisiana I have grown many citrus for many years. Some of the satsuma cultivars can take to about 20F or so with little or no damage and 3+ year old wood to mid teens, and some of the kumquats can take mid teens and 3+yr wood even more. My Washington Navels and meyer lemon can take low 20s. All are grafted on trifolate. When i lived down there i used to drape a sheet over them with a heat lamp for weather in the teens and i think about 11F or so was my coldest temps. The only trees I ever lost totally to cold were key and persian lime and grapefruit, those are less hardy.


In 7b North Carolina, we move our Key lime, Meyer lemon, and Ichang lemon in and out depending on the winter temps. We’ve had 8 key limes and 10 lemons on our 3 year old trees this year. The lemons are still ripening on the tree and they will probably do some ripening indoors.
In Raleigh, there’s a huge cold hardy citrus tree in Raulston Arboretum, I’ve never asked what the variety is, but it’s at least 15 feet tall and always covered in big lemons in the wintertime.
@PaulinKansas6b, is your Meyer lemon in the ground?


Yes it is inground. I havent done anything to it in years. But the ground will get a lot colder in 7b than 8b so if you put in ground in 7b it may need more warmth than 8b needs.


Sour citrus can be harvested much earlier than sweet citrus. Citrangequats are juicy enough by August or September. So those are earlier, and I’ve never had to protect fruit until the low 20s. Even sweet oranges can handle 32 degrees easily. I have had ichangs with lemons in the past ignore 21 degrees with no leaf drop.


@manfromyard, where are you located? I see you’re also in 7b, do you have Ichangs in the ground? Don’t the lemons get ruined in the 20 degree weather?


kdegs, the orange tree in Birmingham Alabama is routinely exposed to temps below 20 degrees. There is no reason to bring Ichang indoors until temps are below 20 and probably would be ok down to 12 degrees. This applies to larger trees. Seedlings might be injured though less likely with cold hardy varieties.


There was a trifoliate tree growing here in southern west-central KY, in-ground, in an open courtyard on the campus of Hopkinsville Community College, across the street from my former office…probably planted around 1970, it fruited heavily for the 10 years or so that I knew of it until the Easter Big Freeze Disaster of 2007 killed it…but not the ‘lawn’ of closely mown seedlings growing underneath it.
I gave a couple of Flying Dragon seedlings to a coworker here several years back…they’re growing rampantly and fruiting prolifically in her backyard garden.


I need to get ahold of some trifolate seeds. Id think there may be potential for some decent hybrid lemon fruit if effort was put into acres of trifolate seed plantings as has been done with the hybrid persimmon.


Well I can provide seed.
I agree , their is potential here, but this is quite the project .!
My trifoliate are outside and very hardy, but the bloom times don’t generally overlap with my indoor variety collection .
So I have not made crosses.
It would be the potential crosses that you would want to grow out for evaluation.
This is a very thorny project.
Maybe best as a perimeter hedge / fence. And would make a VERY impenetrable fence.
Would require a excavator with steel tracks to remove.
Maybe growing out seeds from a trifoliate from the south ,that was surrounded by other good varietys for pollination would be easyer. Most seedlings will be nucellar, and identical to the parent
May be able to select promising seedlings by leaf shape befor they fruit?
I have a collection of the hardiest citrus / hybrids I could find.
None of which have been hardy out side here ,zone 6 Wv.
Whith out protection. Thomasville has survived several years outside befor dying.
My trifoliate are hardy and productive, just to bitter to use.
I do think there is potential for a cold tolerant citrus,
Good luck


So no luck for me to grow one in Z5 even with protection?


Just picked and drank the juice from my first …
Dragon lime.
The juice was defiantly acceptable . Nothing to brag about.
But nothing bad either , NO bitter in the juice.
I did bite into the peel ,just to see , and it has left a bad aftertaste in my mouth.
Also got some seed to plant !
The plant looks like flying dragon, with the curved thorns, curved stems , trifoliate leafs.
Have no idea how cold hardy this is.
Very little info on the net about this variety.
I have kept it inside during the winters.
Will plant one outside when sufficient size to test for cold tolerance.
Does anyone else have a report on “dragon lime” ?
Got mine from Stan, he says it does good for him.


Dragon lime


@tonyOmahaz5 [quote=“tonyOmahaz5, post:74, topic:13564”]
(“So no luck for me to grow one in Z5 even with protection?”)
Trifoliate orange " may " survive where you are.?
Just not very useful, only as ornamental / conversation piece.
The fruit as very bitter.
Thomasville is the hardyest useful citrus I have found.
It’s good !
And you could likley grow one in ground using " your" methods of protection ( xmas lights, heat, wrapping )


Do you have a website to order it or do you have any seeds for trial?



You may have trouble ripening "all " the fruit before cold sets in.,as some will be late


OK this grabs my attention.

Is it serviceable as something you squeeze onto your food or mix with soy sauce, or just as a replacement for calamansi juice?

BTW if you are ever in New England, Logee’s is a neat place to check out. Ever since I learned about it I’ve tried visiting once or twice every winter.