Hello - I have a pygmy date palm that up until this year has been very healthy looking. I noticed in the last week or two that some of the fronds are yellowing in some areas (not the lower fronds). I do fertilize this palm. It is worth noting that we had a winter in which it reached the mid 20's a few nights down here, causing a lot of stress on plants (or death).

This plant faces East, plenty of light, watering is good (as mentioned, it's never had any issues). Basic ol' central coastal Florida soil.

Is this leaf blight (I precautionary treated with liquid copper)?

My guess is micronutrients. Someone like @Merlyn who knows the soils and minerals in the area can give a more educated opinion.

If the palm is well watered , fertilized , and established it should grow out of it . Perhaps a bit of cold damage . As the new fronds open , they will tell you unless the growth point was damaged. Harry

Thanks! I did check the new fronds and they look nice and happy.

I usually see Potassium deficiency as a common problem with Roebeleniis in Merritt Island. Yours looks like it could be that. It will show on the oldest fronds as an orange/yellow with burnt tips. What fertilizer are you using? You might want to add some K Mag which is potassium and magnesium. Usually it will have a ratio of 2:1. It is available at Site One in Rockledge. The old leaves will not improve with treatment. It is only going to help the new growth.

Kmag or sulpomag or langbeinite are all the same stuff. It doesn't quite look like a typical Magnesium deficiency, as it's more splotchy and not just at the leaf tips. Potassium deficiency does tend to look splotchy. I'd think some kmag is a good choice.

It doesn't look like a fungus to me, being only on the oldest fronds. Palms "eat" the old fronds for nutrients, so things like Magnesium and Potassium show up there first. But I would check the leaves for any signs of bug bites, just in case. Some of the splotches look like they could have a central starting point. Mealybugs or hard scale could cause similar splotches.