Growing olive trees in marginal zones

Hi folks! I’m curious if others have tinkered with growing olives in-ground in cold-ish climates. I’m in high desert zone 7b. I plan on experimenting with putting a mission or arbequina variety in a heat trap patio area. I’ve managed to grow figs in that area with no cover so I thought I’d try figs’ spiritual ally, olive.

I’ve got a few questions for those who grow olives- first, what kind of damage do they experience in the cold? Figs for example will die back to the roots if I manage to screw up- It’s never gotten cold enough to kill them completely here. Is the same true of olive? Will it sprout from the roots, and are those roots hardier?

I’m also curious if folks have tried cover for them- some of my figs get wrapped with burlap and covered with leaves for the winter and that works quite well. Im wondering if it would be possible to do that with olives or if the evergreen nature would preclude it.

Thanks for entertaining my questions!

Alder,

It took me a couple of days to get to your post and I apologize for that.

I live in a very humid zone 6b and I had a neighbor plant a fig tree and grow it successfully till he moved.  As far as I know he didn’t do anything special to it, but I wasn’t exactly watching him.

As far as the Olive tree goes, my suggestion would be to just try it as see what happens.  You will be a sort of pioneer!  But maybe protect the roots with some straw?  I am just guessing on that one, but it might be worth considering.

At any rate, good luck and please keep us informed.  I would love to hear how this would out.

Eric

Wow, zone 6! Amazing. There are rumors of olives around here too but I haven’t met any of their caretakers yet.
I’m thinking of getting a bunch of barrels and filling them with water to serve as a thermal battery, I can sandwich the tree between the barrels and a south facing wall, and cover with poly, hopefully creating enough of a buffer to keep vibrant.

I'll give you my experience of growing olives such as it is.
I'm not particularly cold here (over winter -5 deg C is normal), but tender plants and trees will die from the wet soil and cold winds in the winter. When we moved here there was an olive tree in a large barrel planter in the polytunnel. I thought I'd killed it through lack of watering one year, there was no leaf growth at all. I evicted the olive, pot and all and it subsequently started growing from the rootball. So although the upper growth was dead it does resprout - I guess it is a form of coppicing. The other thing to watch out for is if the tree is grafted then the scion may die back and regrowth be from the rootstock only. I'm not sure how olive trees are propagated commercially.
I have a replacement olive now which is looking a bit tatty. My tunnel is without a cover at the moment and being evergreen, the leaves have been torn off by the winds over winter. The lower branches look OK though, and I think it will grow back. This one is planted in the ground, and is thriving rather too well. I had to cut it back rather hard to stop it going through the roof.

Alder,

I like the thermal battery idea.  I would make certain to occasionally add in heat (hot water) and insulate the top, bottom, and outsides.  

Slightly OT, but I used to heat my cat’s outside house (a very old doghouse) by placing 3 1-gallon milk jugs filled with hot water and placing an old, somewhat thin blanket over the house.  The cat house sat in our garage which was getting close to -20 Fahrenheit.  Frigid.  After an hour of placing the jugs in I checked on the cat.  I heard a loud rumbling coming from the house.  Inside the house I bet the temperature was 80 degrees!  The cat purred away.

Obviously this heat fades, but by morning the temperature in the house was still cool but comfortable and the water jugs were lukewarm.

Obviously you would want this to last more than a day and I am sure you could devise such a contraption.  Insulation would be key and water/heat would have to be replaced.

Good luck!

Eric