I have had my olive tree for over a year now. It is kept in a pot indoors in a light extension room, and is watered whenever the soil feels dry, every other watering including a diluted solution of olive specific nutrients.
Over the last few months all the leaves in the centre of the tree have been dropping off. I thought it was dying, but now new growth is showing on the outer branches.
I pruned off some of the branches where the leaves were wilting on the entire branch, but more seem to keep wilting.

