Moisture meters are often inaccurate.

Try digging a few inches into the soil and see if it feels damp. Or push a wooden dowel all the way down into the pot, withdraw it after a few seconds and see of soil particles stick to it. If soil particles stick to the dowel, then watering is not required.

Thanks for quick replay.

I have also done those tests and finger test and all of them indicate there is enough moisture in the soil. Not sure problems with watering would produce tiny bumpy deformed fruits either, so don't think moisture levels are issue here.

It looks like my Navel Orange did after not getting enough water for a long time. It had curled leaves and deformed fruit. Are you putting your finger into the soil to test if it has too much or too little? Or try the chopstick test. (http://homeguides.sfgate.com/check-soil-moisture-chopstick-30981.html)

I haven't had any luck with the cheap moisture meters in assessing how much water I need.

edit: hadn't reloaded the page and saw valadamir said the same thing before me. :)

I suspect there is an issue with the roots. Did you repot the tree recently?

I didn't repot it recently, bought tree mid 2015 and it's still in same pot. What issues with roots are you thinking it might be?

If the tree is light soak the entire root ball for several hours in deep water to drive the air out to let the soil rehydrate.

6b Steve

My leaves look similar on my Meyer, someone once told me it could be related to pest damage. Specifically spider mites. I have been treating with HO and Neem but not religiously like I probably should. I will spay them again this weekend and again in 1-2 weeks, then hope that spring and summer bring normal looking growth.

I doubt very much it is spider mites. If it were, you would see tiny webs. Check with a magnifying glass and look for very small insects.

S_milavic:

Keeping the pot inside a slightly larger one, that doesn't have bottom holes, will restrict soil aeration and will keep the roots in a medium with too much CO2.

Life activity in soil uses O2 and produce CO2, that is heavier than the air. So CO2 will fill the larger pot and stay there until you move the inner pot or fill them both with water.

So, use the ceramic pot for something else. Your tree will apreciate a larger pot and some new soil. If you just pot-up, pay attention to use the same soil/medium like the current one.

Thanks for comments!

So basically no one thinks this is some sort of virus, but issue with soil and roots? There is no webbing on tree, so don't think it's mite problem. The larger pot is part of self watering system, with wick going up into soil. But I can see some roots coming out of holes in the bottom of inner pot. I don't know what mix is used now in pot, so can't buy same one to pot-up, but repotting into a bit larger pot and new medium for citrus would help?

Thanks again. I'll buy mix for citrus trees and try to repot and see if it helps

Commercially available mixes for citrus trees with which I am familiar are very water retentive and so care must be used to prevent overwatering and consequent development of root rot.

Thanks again for all comments. I bought citrus mix (don't have option of mixing custom mix in local shop, so had to buy "mediteranian mix" for citrus and olive trees, with all the ingredients Vladimir listed mixed in and some extra nutrients and metals for citrus). Repotted today, and yes, it was basically just roots in the pot, so that was probably causing stress. Took long time to untangle roots, remove old ones, etc., but hopefully this reporting will help plant recover. Anyone knows how long it will take before I can see improvements in the tree?

It can take months, so be patient. Try to keep the pot warm.

Those leaves on the tree may not recover, but they probably will perk up a little. New growth will tell the truth. It could just take month or two before the tree starts kicking in. For now it will build up roots.