First, you did what so many people do with Meyers in containers; you made an abrupt light condition change. Meyers are quite sensitive to such changes and will often drop many leaves to later replace them with leaves better suited to the new light. It looks to me like the two top yellow leaves got burned... maybe too close to the light?
The lower yellowing leaves is reaction to the light change.

Does your container have good drainage?... not clear in the foto. The tree looks very healthy; not like it has been overwatered. In the future, Spring and Fall, when moving the tree, do it from full sun; 2 weeks then to partial sun; another two weeks to full shade; then 2 weeks to indoors; reverse in the Spring and you should avoid the common leaf drop. I would also limit the fruit on this size tree to no more than 5 or 6; any more than that, the tree will "forget" to grow.

Here's a picture of the lemon tree under the 3 fluorescent grow light.

{{gwi:636268}}

You're burning the leaves, Mrs.Leo, that's pretty apparent, considering how close that poor tree is to the tubes! Put your nice tree outside during the day, bring it inside at night if temps are threatening to drop to freezing. Bring it in gradually. Leave it in a bright window. If you feel compelled to give in additional light, then be sure this light is stationed at least 18" above your little tree.

Patty S.

Johnmerr, Thanks for your insight. I think you're right regarding the light issue. We live in the Seattle area and it's started to get cloudy and overcast these past two weeks. We were worried that the tree is not getting enough warmth and light. We were even considering to get an additional grow light last night! As you can see from the picture I just posted, the light is just an inch or two above the tree. Should we reduce to 1 light instead of turning on all 3 for the moment or leave them all off?

The tree was transplanted into this current pot 1.5 months ago. It's supposed to be a self watering pot. I don't use it for that purpose but more for drainage. There are holes on the bottom of the inner pot and I've put some small pebbles on the bottom to facilitate drainage. The tree hasn't really grown any taller since we got it. It looks more like a bush than a tree at the moment. We were hesitate to prune it due to our inexperience. We were also not sure whether we should remove the fruits as well. There are 12 on the tree right now. Thanks for your advice, we will remove some fruits from the tree tonight.

Nice to meet you.

My goodness! I am with Patty and John!

Please, remove that tree from being that close as soon a possible. Have a good night.

Mike