Palm and tree questions
What is the best fertilizer for palm trees in Florida?
The documented UF/IFAS standard for Florida landscape palms is an 8-2-12 fertilizer with 4 percent magnesium plus micronutrients, in controlled-release form. Lawn fertilizer is the wrong product: it is heavy on nitrogen and can make palm deficiencies worse.
Reviewed by Jeff Kaulbars, ISA Certified Arborist FL-10118A, Ptolemy Inc.
What 8-2-12 means
The three numbers on the bag are nitrogen, phosphorus and potassium, as a percent of the weight. A palm fertilizer is low in nitrogen and phosphorus and high in potassium, because potassium is what Florida palms run short of most.
What else it needs
N-P-K alone is not enough. A complete palm fertilizer also carries magnesium, manganese and micronutrients such as iron and boron. An incomplete one can leave the real deficiency uncorrected, or throw the ratios far enough out of balance to start a second one.
Why controlled-release
In sandy soil, a fast-release fertilizer can wash past the roots before the palm uses it. A controlled-release fertilizer lets nutrients out slowly, so more of it stays within reach of the roots.
The bag is only half of it
On high-pH or reclaimed-water properties, the nutrients can be in the soil and still locked away from the roots. Check the soil before adding more product.
Read more
Sources: UF/IFAS EDIS palm nutrition series (EP263 to EP269).