Papaya is a fast, tree-like tropical plant that can fruit within a year of planting, and is grown commercially in a small way in South Florida. It is short-lived and cold-tender, so gardeners farther north often treat it as an annual or keep it in a container. Papaya ringspot virus is the most important disease in Florida, and UF/IFAS suggests replanting every 18 to 24 months because of it.1, 2
When to plant papaya in Florida
Region
Months on the UF/IFAS calendar
North Florida
Apriltransplant with care · Maytransplant with care · Junetransplant with care
Central Florida
Marchtransplant with care · Apriltransplant with care · Maytransplant with care · Junetransplant with care · Julytransplant with care
South Florida
Februarytransplant with care · Marchtransplant with care · Apriltransplant with care · Maytransplant with care · Junetransplant with care · Julytransplant with care · Augusttransplant with care · Septembertransplant with care
transplant (nursery plant or home-raised seedling)
Spacing in the row (inches)
84 to 144 (plant 2 or 3 papayas 7 to 12 feet apart)
Days to harvest
flowering about 4 months and fruit about 7 to 11 months after planting
Plant in full sun at least 7 to 10 feet from other plants, buildings and power lines, in the warmest spot that does not flood. Planting two or three plants makes it likely that at least one bears, since papayas can be male, female or bisexual, and seedlings may be any of these. To start from seed: rinse seeds from a ripe fruit, rubbing off the jelly-like sac that blocks germination; sow 2 to 4 seeds per 1-gallon pot; expect sprouts in 2 to 3 weeks; keep the strongest; feed with dilute fertilizer every 10 to 14 days; and plant out at 6 to 12 inches tall. Nursery plants in 1- to 3-gallon pots should not be root-bound. Where flooding is common, plant on a mound of native soil 2 to 3 feet high and 4 to 10 feet across. Female plants need a male nearby to set fruit; bisexual plants pollinate themselves. 'Solo'-type papayas are also sold but are more susceptible to ringspot virus.
Water steadily: drought makes papaya drop flowers, leaves and young fruit. In sandy or rocky soils, water every other day or daily in hot, dry weather and less often in winter; in loams, about every 3 to 4 days in hot weather. Avoid overwatering by lawn sprinklers, which can rot roots.
Fertilizer
Small amounts often. EDIS HS11 suggests 1/4 pound of a complete fertilizer every 14 days for young plants, increasing as they grow, then 1 to 2 pounds every other month once they are about 7 to 8 months old, plus periodic minor-element sprays and iron (chelated iron drenches on high-pH soils).
Grows and fruits best at 70 to 90 F, in hardiness zones 9B to 11. Root growth slows when soil drops below 60 F; flowering suffers below 59 F; heat above 90 F can drop flowers; and plants are damaged or killed below 31 F. North of the frost-free zone, start with the largest plant you can find, keep it in a warm sunny spot or a movable container, and expect a short life. Papaya grows in sand, loam or rock but not in boggy ground, and wind can topple fruit-laden plants. Do not prune the main growing tip. Mulch 2 to 6 inches deep, kept 8 to 12 inches from the trunk, and keep mowers and string trimmers away.
Papaya ringspot virus: The most important papaya disease in Florida: yellow mottled leaves, distorted leaf lobes, and dark rings or C-shaped marks on fruit. Remove infected plants. HS11 recommends replanting every 18 to 24 months and avoiding seed from small pear-shaped Solo-type fruit.
Papaya fruit fly: Lays eggs through the peel; the simplest control is to cover young fruit with a paper bag or cloth until harvest.
Papaya webworm, papaya whitefly and two-spotted spider mite: Damage fruit, stems or leaves; hose off webworms and remove infested leaves.
Nematodes: Root-feeding nematodes weaken plants and make them prone to toppling; avoid infested ground or grow papaya in a container.
Anthracnose, powdery mildew, Phytophthora blight and Corynespora leaf spot: Other diseases listed by HS11; clean potting mix helps avoid root rots.
Pick green fruit to cook as a vegetable, or for eating fresh once yellow covers about a tenth to a third of the skin; more color on the tree means sweeter fruit. Let it finish ripening at room temperature, then refrigerate. Ripe fruit keeps about 4 to 7 days. A well-kept plant can give 60 to 80 pounds in a year.
In an aquaponics system
We haven't found a published source that covers papaya in aquaponics systems, so this lesson doesn't guess. The planting months above apply to a grow bed the same as to soil; the water does the watering.
What this lesson doesn't cover yet
Neither SRAC 454 nor the FAO manual addresses papaya.
No UF/IFAS seed sowing depth was found.
Your county extension office and its Florida Master Gardeners can fill these in for your garden.