What says "tropical" more than a robust, healthy palm? Palms come in a variety of sizes, frond shapes and colors, mature heights and landscape uses. All require basic, complete nutrition in the soil with the main elements of nitrogen, phosphorus and potassium as well as many important micro-nutrients such as magnesium and iron. Scattering a wide but complete "ring" of a slow-release fertilizer around the broad root zones of palms is an effective way to promote good plant health.
Study the palm. Realize that the roots of the palm extend well beyond its trunk(s). The drip-line, where the farthest reaches of the frond canopy extend, is an approximate guide to determine how far out the roots grow from the trunk(s).
Read the "palm special" fertilizer product label for proper dosages and recommendations.
Put on latex gloves before handling the fertilizer granules.
Measure and weigh fertilizer with a scale and cup or bucket an appropriate amount of fertilizer. Consult the product label. Often it will direct you, for example, to apply 2 pounds of fertilizer for every foot of trunk height, or other similar general guideline.
Take the measured amount of fertilizer to apply to the palm. Scatter the granules with your gloved hand across the soil around the trunk base as well as extending outward to the drip-line of the palm. Avoid piles of fertilizer; spread it evenly and broadly, as if you were scattering lots of pepper and salt on a plate of mashed potatoes.