It is widely grown in the tropics and subtropics by small and large commercial producers, both as grain legume[5] and as an oil crop.

[1] Like most other legumes, peanuts harbor symbiotic nitrogen-fixing bacteria in root nodules,[7] which improve soil fertility, making them valuable in crop rotations.

[11] After fertilization, a short stalk at the base of the ovary—often termed a gynophore, but which appears to be part of the ovary—elongates to form a thread-like structure known as a "peg".

[15][16][17] The initial hybrid would have been sterile, but spontaneous chromosome doubling restored its fertility, forming what is termed an amphidiploid or allotetraploid.

[10] The oldest known archeological remains of pods have been dated at about 7,600 years old, possibly a wild species that was in cultivation, or A. hypogaea in the early phase of domestication.

In West Africa, it substantially replaced a crop plant from the same family, the Bambara groundnut, whose seed pods also develop underground.

According to Bernard Romans, groundnuts were introduced into colonial East Florida by Black people from Guinea, where the plant is also endemic.

[9] George Washington Carver (1864-1943) championed the peanut as part of his efforts for agricultural extension in the American South, where soils were depleted after repeated plantings of cotton.

He invented and promulgated hundreds of peanut-based products, including cosmetics, paints, plastics, gasoline and nitroglycerin.

[26] In Georgia, Naomi Chapman Woodroof is responsible for developing the breeding program of peanuts resulting in a harvest almost five times greater.

[27] Certain cultivar groups are preferred for particular characteristics, such as differences in flavor, oil content, size, shape, and disease resistance.

Until 1940, 90% of the peanuts grown in the US state of Georgia were Spanish types, but the trend since then has been larger-seeded, higher-yielding, more disease-resistant cultivars.

This shift is due to good flavor, better roasting characteristics, and higher yields when compared to Spanish types, leading to food manufacturers' preference for the use in peanut butter and salted nuts.

Sometimes known also as Texas Red or White, the plants are similar to Valencia types, except the stems are green to greenish brown, and the pods are rough, irregular, and have a smaller proportion of kernels.

Apart from nitrogen, phosphorus and potassium, other nutrient deficiencies causing significant yield losses are calcium, iron and boron.

The machine lifts the "bush" from the ground, shakes it, then inverts it, leaving the plant upside down to keep the peanuts out of the soil.

[39] Some people (1.4–2% in Europe and the United States[40]) report that they experience allergic reactions to peanut exposure; symptoms can be especially severe, ranging from watery eyes to anaphylactic shock, the latter of which is generally fatal if untreated.

[51] Raw Valencia peanuts are 4% water, 48% fat, 25% protein, and 21% carbohydrates, including 9% dietary fiber (USDA nutrient data).

According to the US Food and Drug Administration, "Scientific evidence suggests but does not prove that eating 1.5 ounces per day of most nuts (such as peanuts) as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease.

Boiled peanuts are a popular snack in India, China, West Africa, and the southern United States.

[58][59] Extractable from whole peanuts using a simple water and centrifugation method, the oil is being considered by NASA's Advanced Life Support program for future long-duration human space missions.

Peanut flour concentrates (about 70% protein) are produced from dehulled kernels by removing most of the oil and the water-soluble, non-protein components.

Peanuts are also widely used in Southeast Asian cuisine, such as in Malaysia, Vietnam, and Indonesia, where they are typically made into a spicy sauce.

The peanuts are commonly served plain salted with garlic chips and variants, including adobo and chili flavors.

Indian cuisine uses roasted, crushed peanuts to give a crunchy body to salads; they are added whole (without pods) to leafy vegetable stews for the same reason.

Peanuts grow well in southern Mali and adjacent regions of the Ivory Coast, Burkina Faso, Ghana, Nigeria, and Senegal; peanuts are similar in both agricultural and culinary qualities to the Bambara groundnut native to the region, and West Africans have adopted the crop as a staple.

Groundnut stew, called ebinyebwa in Luganda-speaking areas of Uganda, is made by boiling ground peanut flour with other ingredients, such as cabbage, mushrooms, dried fish, meat or other vegetables.

Peanut shells are used in the manufacture of plastic, wallboard, abrasives, fuel, cellulose (used in rayon and paper), and mucilage (glue).

Plumpy Nut, MANA Nutrition,[78] and Medika Mamba[79] are high-protein, high-energy, and high-nutrient peanut-based pastes developed to be used as a therapeutic food to aid in famine relief.

The World Health Organization, UNICEF, Project Peanut Butter, and Doctors Without Borders have used these products to help save malnourished children in developing countries.