Discoloration on leafs need help identifying cause

[Susanne42]

I bought an Pro Blanco Four years ago. It looks like it wants to grow but it is stuck. Some of the leafs show some brown kinda layer along the veins. What am I dealing with? can not find any info. But have the feeling I need to do something. Thank you for any help.

[Millet]

Never seen symptoms as shown on your tree's leaves.  My impression is that it might be caused by something through root up take.  Have you applied anything different to the soil?

[Susanne42]

no, nothing new. I fertilize with organic citrus fertilizer and cheleated iron this spring because not diligent with feeding last year (foliar spray) as I had pale leafs. I just don't remember when this showed up as this is only on last years leafs and they do not look like they will fall off anytime soon. Re-potted a week ago and roots looked healthy as much as I could see. Lots of white tips, nothing mushy or falling appart. Wish I would have took picture of the roots.

[Millet]

I take it you actually meant Oro Blanco (you wrote Pro Blanco).

[Susanne42]

ups, yes, oro blanco

[Millet]

If the new leaves are growing out without the brown center vain, but rather look normal, I would not worry about it much.