Capsicum

Aji pepper is the South American chili species behind aji amarillo, Lemon Drop, Bishop's crown and Brazil's dedo-de-moça - one of the five domesticated chili peppers, and a different plant from the familiar garden pepper (Capsicum annuum) and the habanero (Capsicum chinense). It is a perennial shrub native from Colombia, Ecuador and Peru through Bolivia, Paraguay, Uruguay, northern Argentina and central and southern Brazil, and where it can live for years it grows taller than most garden peppers, up to about 6.6 feet. Its white to cream flowers are typically marked with green or gold, and its fruits, which usually hang down in cultivated forms, come in an unusually wide range of shapes, from long tapered pods to the crown-shaped Bishop's crown. Heat runs from nearly heatless types to hot ones; aji amarillo is rated around 30,000-50,000 Scoville units. It is frost tender, so outside nearly frost-free climates it is grown as a warm-weather annual.

A warm-season vegetable producing sweet bell, hot cayenne, jalapeño, paprika, and ornamental cultivars all from a single species - capsaicin content varies dramatically across cultivars while the plant itself remains uniform in habit (compact mounded warm-season annual). NC State documents capsaicin-immune birds as opportunistic fruit consumers; self-pollinating with optional cross-pollination from bees increases fruit set.

A tropical, frost-tender pepper grown for some of the hottest fruits in the kitchen garden - this single species includes the habanero, Scotch bonnet, ghost (bhut jolokia), and Carolina Reaper. Native to the Americas (the Amazon basin and the Caribbean), Capsicum chinense is a true perennial only in frost-free zones 10-11; across nearly all of North America it is grown as a heat-loving warm-season annual. It needs a long, hot season to ripen its lantern-shaped fruits, and the capsaicin in those fruits is potent enough to burn skin and eyes, so it rewards a sunny spot and careful handling.