Southwest Florida's sandy, alkaline soils don't hold onto the nutrients palms need, so yellowing fronds are common. The pattern of the yellowing tells you what's missing.
Reading the fronds
Potassium deficiency shows on the oldest, lowest fronds as translucent yellow-orange spots and frizzled, dead tips. It's common on foxtail and royal palms. Magnesium deficiency shows as a broad yellow band along the edges of older fronds, with green in the middle. Manganese deficiency shows on the newest fronds, which come out weak and frizzled ("frizzle top"), especially on queen and royal palms.
Feed the right way
UF/IFAS recommends a palm fertilizer with an 8-2-12-4Mg analysis plus micronutrients, with the nitrogen, potassium and magnesium all in slow-release form, applied about three to four times a year. High-nitrogen lawn fertilizer near palms can make potassium deficiency worse.
Don't over-trim
Older fronds feed the palm potassium as they yellow. Cutting green or partly yellow fronds, the "hurricane cut," speeds up deficiency and weakens the palm. Remove only fully brown fronds.