quercus suber (cork oak) frost hardy or not?

[Linn01]

Recently bought one in the south of France. Is not even a pre-bonsai but it may have potential. Will post a pic later. Is still in its original soil as bought. Not going to touch it until spring (repot scheduled).

In order to make sure it survives the winter, I wonder if this tree can remain outside during winter. Seldom gets colder than - 10°C here (14°F). Anyone some advice on the hardiness of cork oaks?

 

[Shibui]

Cork oak grows here just fine down to -5C minimum.
Also in Canberra down to -6 or -7C.
My guess is that it should cope with your -10C but let's see if anyone has direct experience.

 

[Bonsai Nut]

I have had no trouble keeping several cork oaks outside in my area over the last two winters. The trees remained on bonsai shelves and did not seem at all bothered by the cold. However even though it gets cold at night, there is not a single day that does not get significantly above freezing, and the soil here never freezes hard.

I also have a number of olive trees (from the same native area) that I leave out as well. The olives haven't been bothered by my winters either.

I am zone 8a. I plan on leaving them outside again this winter.

 

[Lutonian]

I have about 15 cork oak seedlings in small nursery pots growing outside with no protection for the last three years (gone through two winters) and no cold weather fatalities yet they have gone down to about -8c or-9c

they are grown out side in kew garden in London and here is a list of the largest ones growing in the uk with there locations and pictures https://www.monumentaltrees.com/en/gbr-quercussuber/england/

 

[luvinthemountains]

I am in zone 7a here, and finally gave up on keeping cork oak this year. It was only marginally surviving here, so I would guess the boundary line is somewhere between zones 7 and 8.