Care Guide · Blackout-Compliant · Updated 2026
Palm Fertilizer Schedule for SW Florida
Ninety percent of the "sick" palms we get called about are just hungry. Here is the exact program we run — what to buy, when to spread it around the Lee County blackout, and how to read what your palm is telling you.
Cape Coral's soil is sand over shell fill: alkaline, fast-draining, and nearly empty of the potassium, magnesium, and manganese that palms burn through. Every yellowing palm on your street is telling the same story. The good news — the fix costs a bag of fertilizer twice a year and about twenty minutes.
The Blend: 8-2-12 with 4% Mg
Buy a slow-release palm fertilizer labeled 8-2-12-4Mg with micronutrients (manganese, boron, iron) — the formulation developed by University of Florida research specifically for Florida palms on our soils. The numbers matter: high potassium (the 12) because that is our most damaging deficiency, low phosphorus (the 2) because our soil already has enough and the canals do not want more, and slow-release so one application feeds for months instead of washing into the storm drain with the first afternoon thunderstorm. Skip generic lawn fertilizer entirely — the high-nitrogen, no-potassium mix actively worsens palm deficiencies.
The Calendar — Built Around the Lee County Blackout
Lee County's fertilizer ordinance prohibits applying nitrogen or phosphorus fertilizers from June 1 through September 30 — the rainy season, when runoff goes straight to the canals and the Caloosahatchee. Cape Coral and Fort Myers enforce it, and it is good practice besides. So the schedule is simple:
MAY — the big feed
Full application of 8-2-12-4Mg before the blackout starts. The slow-release prills keep feeding through the summer growth flush legally and effectively.
JUNE–SEPTEMBER — blackout
No N or P applications. If a palm shows acute magnesium or manganese deficiency mid-summer, targeted products without nitrogen or phosphorus (e.g., magnesium sulfate, manganese sulfate) remain an option — that is also how we treat frizzle top in season.
OCTOBER — the second feed
Second full application when the blackout lifts. This carries palms through the dry season and is the one most homeowners skip — it shows by February.
RATE & METHOD
Follow the bag rate (typically about 1.5 lbs of product per 100 sq ft of canopy area), broadcast evenly under the entire canopy and a couple of feet beyond — never piled against the trunk — then watered in lightly. Feed the whole root zone, not a ring at the trunk.
New installs: we include starter fertilizer at planting. Begin the regular schedule at the next calendar window rather than double-feeding a fresh transplant.
Reading the Fronds
Potassium (most common): orange-yellow speckling and dying tips on the oldest fronds; severe cases look scorched from the bottom of the crown up. Magnesium: broad yellow bands along the edges of older fronds with a green center stripe. Manganese ("frizzle top"): the dangerous one — new growth emerges weak, yellow, and frizzled; hits queen palms hardest (their whole sad story is in our queen palm guide) and untreated it kills the palm. Iron: yellowing on the newest fronds, typically on palms planted too deep or in waterlogged spots — a planting problem more than a feeding one.
The rule that saves palms: never remove yellowing fronds. Palms cannibalize old fronds for mobile nutrients — cut them off and the deficiency simply moves up the crown. Trim brown, dead material only, and fix the feeding.
Species Notes
Royals, coconuts, and queens are the heaviest feeders on this program — skipping the October application shows on them first. Foxtails and Montgomerys are moderate; sabals and saw palmettos barely care. Areca hedges deserve special mention: a yellow areca screen is almost always hunger, not disease, and greens up two months after a proper feed. Installed prices for all of these are published on our palm pages — and every install comes with this feeding schedule in writing.
Fertilizer FAQ
What fertilizer should I use on palms in SW Florida?+
An 8-2-12 slow-release palm blend with 4% magnesium (often labeled 8-2-12-4Mg) and micronutrients including manganese. It is the University of Florida-developed formulation for exactly our sandy, alkaline soils, and it is what we use on our own installs.
When is the Lee County fertilizer blackout?+
June 1 through September 30. During those rainy-season months, applying fertilizers containing nitrogen or phosphorus is prohibited in Lee County (Cape Coral, Fort Myers, and unincorporated Lee) to protect the canals and the Caloosahatchee. Feed in May before it starts and October when it ends.
Why are my palm fronds yellowing on the older leaves first?+
Bottom-up yellowing is usually magnesium or potassium deficiency — the two most common shortfalls in Cape Coral sand. Yellow banding on older fronds points to magnesium; orange-yellow speckling with dying frond tips points to potassium. Both are fixed by the 8-2-12-4Mg schedule, not by cutting the fronds off.
Should I cut off yellow palm fronds?+
No — palms pull mobile nutrients out of old fronds to feed new growth, so cutting yellowing fronds removes the palm's nutrient reserve and makes deficiencies worse. Trim only fully brown, dead fronds. Fix the feeding and the new growth comes in green.
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Rather Have Us Handle It?
We plant palms with the right start and can point you to exactly what your existing palms need — text a photo of the fronds and we'll diagnose it free.