Almond

The almond (Prunus amygdalus, syn. Prunus dulcis) is a deciduous tree species within the genus Prunus, classified alongside the peach in the subgenus Amygdalus. This subgenus is distinguished from others by the corrugations on the woody shell, or endocarp, that surrounds the seed. The tree can reach a notable height, with a trunk of considerable diameter. Its young twigs are initially green, turning purplish when exposed to sunlight, and become grey in their second year. The leaves are serrated along the margin and grow on a petiole. In early spring, fragrant white to pale pink flowers, each with five petals, appear singly or in pairs before the leaves emerge. The almond prospers in a moderate Mediterranean climate with cool winters, and its buds require a specific period of chilling to break dormancy. It begins bearing an economic crop in its third year, reaching full production after five to six years, with fruit maturing in autumn, several months after flowering.

The fruit is a drupe, not a true nut, consisting of an outer hull—a thick, leathery, grey-green coat—and a hard, reticulated shell inside. Within this shell lies the edible seed. After maturation, the hull splits, and an abscission layer forms, allowing the fruit to fall. Mechanised shakers are used during harvest to expedite this process. Almonds are sold either shelled or unshelled; blanched almonds are treated with hot water to remove the outer skin, revealing the white embryo. Once processed, they can be stored for about a year if refrigerated, as higher temperatures accelerate rancidity. They are used extensively in cuisines, particularly in desserts like marzipan.

Almonds were among the earliest domesticated fruit trees, a development facilitated by their ability to produce quality offspring from seed alone, without the need for suckers or cuttings. Evidence of domesticated almonds dates to the Early Bronze Age in the Middle East, from where cultivation spread across the Mediterranean and into similar arid climates with cool winters. Today, California supplies roughly 80% of the world’s almonds, though this production faces sustainability challenges due to high water and pesticide demands, exacerbated by persistent drought and heat from climate change in the 21st century. These conditions have led some producers to leave the industry, reducing supply and increasing prices.