Treating Olives as Tropicals over winter

[darzuo]

I recently got a couple of olives (europaea sylvestris I believe) and am considering my options for winter. I know they can be quite cold hardy, but I'm not sure they can tolerate the coldest temps in my zone even with root / wind protection. I've heard some back and forth about whether they truly need dormancy and was wondering if they would be fine with either the rest of my tropicals in a high-humidity grow tent. Do they need dormancy to thrive?

Let me know your thoughts / experiences. Thanks!

 

[Dav4]

When I moved from GA to MI, I tried to overwinter my Olive in my attached garage where the temps stay in the 35-40 F area for about 3 months... it took 3 years for it to regain close to half of the vigor it lost after that winter, and has never regrown all the inner branching that it dropped. I now keep it under lights in my study and it grew quite well for the first summer in 4 this year.

 

[Michigan Tree Murderer]

I try to give mine 40 days of dormancy in the 40 degree range, and then I treat it like a tropical in the basement under lights for its "winter". @Dav4 has a sweet olive.

 

[KWag]

Zone 7. I’ve always kept my two olive trees inside when night time temps hit 40 degrees. 16 hour of light. Then when temps come back to the 40s I set them in the garage/carport on the south facing brick wall and keep a blanket handy.
I do the same for my pomegranates.

 

[Desert O'Piñon]

I am in a much warmer zone, but I do have an olive (not even pre-bonsai yet) that has overwintered outside the last two years with no winter protection. We regularly have a week at a time around 20° F overnight, reaching 35° to 50° during the days in those stretches. It has had some minor tip burn, but only a few leaves deep. Of course, it's in a very large pot with fairly dense soil at this point, so it could technically be argued that this could qualify as "protection." Don't know if this helps, but you were asking, so I thought I'd share my experience.

 

[BonsaiPoppie]

Zone 10, I don't have to worry about Olives here. The little town here stared out as Olive orchards until Avocados took over.

 

[hemmy]

I think it might be variety dependent on the best practices. I've been trying to figure out the best winter olive setup for a couple years now since moving to a colder zone. They used to live outside where 42F was the coldest temp. Now we get sub-zero temps, so I've tried treating them like both tropical or "Mediterranean" plants. Some shohin small leaf olives have stayed in our living space on a stand under T5 light with good sunlight until Dec. and then gone into to the garage under LED and T5s where the temps are 65F-45F. These are small leaf varieties from bonsai nurseries.

Another small leaf shohin went into the tropical tent 70F-60F, but it was crowded and got microscopic scale so badly that it lost branches and vigor. Another larger leaf variety from a standard nursery, went into the tropical tent and it has not grown strongly this year. I will keep it in the cooler garage under light this year.

 

[darzuo]

Thanks for all the replies, I think I'll try my luck with the grow tent for now and keep an eye out for pests