Peanut Cultivation

The peanut (also called groundnut) is a small annual plant belonging to the legume family. It contains seeds rich in oil, making it a source of cooking oil and cake used as livestock feed. The peanut plant flowers above ground, but the pods develop underground, as the flowering stem bends downward after pollination and pushes into the soil.

Peanut farms are found in warm and semi-arid regions, particularly in Southeast Asia, China, and Africa. Many African countries rely on peanuts as both an export crop and a food source. In Somalia and the Horn of Africa, peanuts are grown in areas with river access.

Cultivation Requirements

Peanuts prefer loose, well-drained soil, since hard, waterlogged soil prevents pod formation and harvesting. Moderate temperatures are generally suitable. Rainfall or irrigation is essential during flowering and pod development; drought during these stages significantly reduces yields. Like other legumes, peanuts associate with rhizobia bacteria in root nodules, which capture nitrogen from the air and improve soil fertility.

Harvesting and Post-Harvest

Harvesting begins by uprooting the plant and then digging until the pods are extracted. Proper drying is an important step, because peanut kernels can promote growth of the fungus Aspergillus flavus, which produces aflatoxin—a toxic compound that poses a health risk and restricts peanut trade in many countries.

Oil Production

Peanut oil is extracted by two main methods: mechanical pressing and solvent extraction, typically using hexane. The crude oil is refined to adjust color, odor, and taste. The residual material, called cake or oilcake, is protein-rich and used as livestock feed. Peanut oil has a high smoke point, making it popular for frying.