And a shot of light green leaves

That doesn't look like iron deficiency, but more nitrogen deficiency to me. What citrus fertilizer are you using and how frequently are you fertilizing? The brown leaf looks like a chemical burn to me. How did you apply the liquid iron? I would make sure you have a very well draning potting mix, lots of light (possibly needing supplemental light), appropriate fertilizer (most indoor citrus folks here will use 1/2 strength DynaGro Foliage Pro with every watering).

Patty S.

Pretty much all leaves that got dropped so far have similar brown marks... I wonder, if it was chemical root burn from iron application, could it take 5-ish weeks to kick in?

Using Romeo 24-14-14 that was recommended by the place where we originally got the tree, a teaspoon per gallon, every two weeks.

As for liquid iron, again went with original recommendation - if I recall correctly that was 1 oz per gallon.

Yikes! That's REALLY high in N, even for citrus,Very strong fertilizer, I think rather overpowering for a container plant, personally. And yes, I would say this may be nitrogen burn. I would re-pot, flush the roots and switch to DynaGro Foliage Pro. Be sure you've got a well-draining potting mix. Some of this may also be due to wet roots. Most container folks use 1/2 strength Foliage Pro with each watering, full strength during the later spring and summer, when citrus are outside and really growing.

Patty S.

Ugh! It looks like it might be repotting it on the weekend :) Thank you!