Hi, about two weeks ago I received a ponderosa lemon for my birthday. When I got it, a couple of leaves were slightly curled/cupped inward. I just thought it was shipping stress and didn't think much of it. I kept it in partial shade for a week, then moved it to a large SW window, then finally outside yesterday. But now a lot of leaves are like this and seem pretty dry. I discovered two scale on it a week ago and rubbed a diluted rubbing alcohol/water mix on every leaf, even though I haven't seen any crawlers. I wasn't sure if this was over/under watering, hidden scale, the alcohol on the leaves or what. Can anyone help?




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Not caused by scale.
To me looks simply like lack of water - although I don't know if the alcohol could perhaps have a similar effect.
How often has it been watered?
Move a bit of surface compost - is it damp underneath?
If not, I would soak the whole thing in a bucket of slightly warm water for an hour or two - then leave to drain.
We are often warned about overwatering citrus, but at this time of year they need frequent watering - especially if in a very free draining mix.
Yours looks very free draining, and very dry.

I agree it looks a little dry. Maintaining proper moisture is key to keeping the tree from dropping fruit-- from bloom to the end of June keep them a little wetter than normal. At other times of yr I would not worry about the amount of leaf curl you have.