Cinchona officinalis aka Lojabark

Cinchona officinalis belongs to the coffee family, Rubiaceae. This evergreen tree comes from southern Ecuador, in western South America. People call it lojabark, loxa bark, and Peruvian bark. It grows in cool, damp mountain regions. Its native home lies at 3,940–9,840 feet [1,200–3,000 metres]. People now grow it in many tropical regions. Both wild trees and those people grow yield its valued bark.

Garden sources give its height and spread as 26 feet [8 metres]. It grows at a moderate rate and keeps its leaves year-round. Broader accounts list shrubs or trees reaching 20–66 feet [6–20 metres]. That range exceeds the size listed for garden plants. Its woody form may suit coppicing, which means cutting stems back for new growth. Growers can raise new plants from seed or stem cuttings. Sources list both softwood cuttings and half-ripe cuttings for this purpose.

This tree needs moist soil that drains well. It grows in full sun or part shade. Sandy soils and loam both suit its needs. It prefers a soil pH of 5.5 to 6.3. It can cope with values from 4.8 to 7. Growth suffers on ground that fire has laid bare. It prefers daytime warmth of 14 to 23°C. Cold of 7°C or below may kill it. PFAF lists USDA zones 10–12, but growers must heed its weakness to cold. It favours a wet climate with plenty of rain year-round.

People have long used the bark as medicine. Indigenous people in South America used it for fever and other ills. The bark contains alkaloids, including quinine and quinidine. Quinine has a proven role in treating malaria. Heavy demand once led people to strip bark from many wild trees. Farms later grew trees to help meet the demand for bark. Man-made drugs replaced much of its use in the twentieth century. Malaria that resists drugs later sparked fresh interest in quinine. These uses make it a crop for medicine, not food.

Quinine taken from bark gives tonic water and other drinks their bitter taste. It also has uses in hair products and insect-killing products. Other uses include work with rubber and the preparation of some metals. These uses do not make raw bark safe to eat. Too much can cause headache, rash, and stomach pain. Severe poisoning can harm hearing and sight. Some countries curb use of the herb or quinine taken from it.