Anacardium occidentale aka Cashewnut

Anacardium occidentale, or cashew, is an evergreen tropical tree. It belongs to the Anacardiaceae family. Kew places its native range from Trinidad to tropical South America. UF/IFAS identifies northeastern Brazil as its place of origin. There, it grows in dry forest and open woodland. People now grow it across the tropics for food. It also grows in home gardens and plant collections.

Garden trees reach about 20–39 feet [6–12 metres] tall. Poor conditions can limit height to 15–25 feet [4.6–7.6 metres]. Useful Tropical Plants reports heights up to 49 feet [15 metres]. Crown widths range from 39–66 feet [12–20 metres] in PFAF accounts. The trunk can be short and crooked. Smooth brown bark covers it, and branches start near the ground. Low limbs may root where they touch the soil. Green, leathery leaves grow in an alternate pattern along stems. Each has clear veins and a broad, rounded tip.

Small, sweet-scented flowers grow in branched clusters at stem tips. Their petals may be white, pink, or red. Petals turn pink and bend back as flowers open. Each cluster holds male flowers and flowers with both sexes. Flies, bees, ants, and wind can carry the pollen. The tree can also set seed with its own pollen. The true fruit is the kidney-shaped nut beside the fleshy cashew apple. People eat the apple raw, cooked, or dried. They also make juice and spirits from it. Its flesh can taste tart and feel fibrous or astringent.

Cashew needs sun and a warm climate without frost. PFAF lists USDA zones 9–12 but stresses its frost sensitivity. It grows in sandy, loamy, or clay soils with good drainage. It can cope with poor soil and drought. Moist soil supports growth, while a distinct dry season suits cropping. Deep soil allows a long taproot to form. Wide lateral roots extend beyond the crown. This root system can make transplanting hard. Sources describe its growth as slow.

Growers use cashew for food, living fences, and erosion control. Its wood, gum, and oil have other practical uses. Leaves and bark also have traditional medicinal uses. PFAF lists leaves and shoots among its edible parts. Seeds need proper processing before people eat them. Nut shells contain poisonous oil that can cause severe blisters. Sap may also cause skin reactions, and burning produces poisonous smoke. UF/IFAS warns against shelling home-grown nuts for food.