Q.My olive tree
I have an Arbequina olive that I put in a pot last year when I received it. Since I live in Northeast Ohio: this past winter I moved it to the basement and put it under grow lights for approximately 14 hours a day. The existing leaves fell off and I started to develop new branches up at the top by the lights. In the spring I moved the potted tree out to the sunniest and warmest part of my yard. I have the same branches as in the basement, but I do not see and new leaves coming out. Am I wasting my time or do I need to have more patients with this tree?
Check the branches; do the bend or snap off?
If they break off, they have died. You can prune off any dead branches and wait to see if you get any new growth from the roots.
https://www.gardeningknowhow.com/edible/fruits/olive/growing-olive-trees-in-containers.htm