Peanuts are actually not a nut but a legume, meaning they grow below ground rather than above ground, on a plant or tree as a nut does. The peanut plant develops flowers, then when the flower withers it turns into a ‘peg’ which then turns downward until it penetrates the soil and eventually grows into a peanut.
Crucially, peanuts can only be grown in frost-free conditions, which therefore dictates the countries and regions they can be farmed in – e.g. California in the USA and African countries including Nigeria and Sudan.
Special machines are used to pull the peanuts from the ground when they’re ready to harvest, which takes place in the autumn months. At this point the peanuts are actually quite moist, but are then cured by a process which uses warm air.