Peanuts are low, self-pollinating legumes with an unusual habit: the flowers bloom above ground, then the developing pod (the 'peg') grows down and the nut matures underground. Runner types, grown commercially across the Southeast, also suit home gardens. The tricky part is timing the dig, because the pods do not all mature at once.1
about 135 to 155 for runner types; about 120 for the Spanish type 'Star'; as little as 75 for Valencia types dug green for boiling
Gardening Solutions: in North and Central Florida, plant from March through May. Plant raw peanuts still in their shells, which germinate fastest, and prepare the soil as for any other vegetable. Coating the seed with a peanut inoculant (nitrogen-fixing bacteria, sold at seed stores) is advised. 'Florunner' and 'Sunrunner' are runner types, 'Star', 'Tifspan', 'Sancross' and 'Tamnut 74' are Spanish types, and 'Florigiant' is a large-seeded Virginia type suited to roasting.
Like other legumes, peanuts make their own nitrogen with help from root bacteria. They do need calcium for the nuts to fill: spread agricultural gypsum beside the row just after plants bloom.
Plants keep flowering, but the earliest pegs mature more slowly than later ones, so the crop tends to be ready together.
Tomato spotted wilt virus: Peanuts are susceptible.
Leaf spot and rust: Leaf spot is a major disease; Gardening Solutions says some garden-vegetable fungicides can be used on peanuts, and that high yields generally need fungicide every two weeks.
Insect pests: Peanuts attract many garden pests; most common vegetable-garden insecticides can be used, but check the label for peanut directions.
Pods do not all mature together. Before digging dry-type peanuts, open a few pods and look for seeds turning darker, a sign of maturity. Lift plants with a pitchfork. For dry peanuts, pile the plants loosely so air moves through and let them cure 5 to 10 warm, rain-free days, then pick off, wash and roast. Valencia peanuts for boiling are dug green and boiled fresh without drying.
Neither source mentions peanuts. FAO says many legumes, 'such as peas and beans', have low nutrient demand (p. 92), but nothing it says covers a crop whose pods must grow down into soil.
What this lesson doesn't cover yet
Only one UF/IFAS source (Gardening Solutions) was found; peanuts are not in the SP 103 planting table and no EDIS home-garden peanut document was fetched.
No South Florida planting window, sun, soil pH or watering guidance was found.
The Gardening Solutions page contradicts itself: it says harvest can begin within three months of planting, but also gives 120 to 155 days for the varieties it lists.
Your county extension office and its Florida Master Gardeners can fill these in for your garden.