Florida is well-known for growing citrus fruits. The sunny, warm to temperate climates in the central and southern portions of the state support a range of citrus fruits from grapefruit to oranges and tangerines. These can be grown both in home gardens and in commercial orchards. According to Mohammad Rahmani and Alan W. Hodges at the University of Florida, commercial citrus production in Florida topped $8 billion dollars in 2007 to 2008. Home grown citrus trees benefit from a life-long regimen of fertilizing, just as those grown in commercial orchards do.
Choose a citrus food or "Citrus Special" tree fertilizer with a guaranteed analysis of 6-6-6 or a similar ratio that also contains micro-nutrients such as magnesium, manganese, iron and zinc.
Feed citrus trees three years and older, four to five times each year, with the dose of fertilizer recommended on the label. The University of Florida warns gardeners not to exceed 20 pounds of citrus fertilizer, per tree in a year. Feed young citrus trees, three years and younger, lightly, once a month or every other month with 50 percent of the label recommended dose of fertilizer.
Put on a pair of garden gloves and cast the fertilizer grains evenly over the soil in a wide doughnut shape around the tree. Keep the fertilizer away from the trunk and extend it to just beyond the drip line of the longest branches to cover the entire root zone.
Work the fertilizer grains into the top inch of soil with a soft rake and water well to move the nutrients toward the root zone. Drench the soil evenly until it is wet at least 3 to 5 inches down.