Cempoalxochitl: the Mexican flower the world calls African
The marigold of Mexican gardens and Mexican graves was described as a medicinal herb of New Spain in the Mexican imprint of 1615 that carries Francisco Hernández's survey, reached Europe in the sixteenth century out of Mexico, and is now grown on thousands of hectares worldwide as the industrial source of lutein. It travelled under names — African marigold, cravo de defuntos — that record everything about its later career and nothing about where it came from.
Why this wins its question: Ask where the marigold comes from and the answers on offer are a garden-centre note that "African marigold" is misleadingly named, or a Day of the Dead feature with no source earlier than the twentieth century. Neither quotes a sixteenth- or seventeenth-century text. This object opens the 1615 Mexico imprint at the chapter headed "DE LA LLAMADA CEMPOALxochitl, yerua" and prints what a book written for estancias and mines without a physician actually says the plant was for — a bitter root decoction, the bowel, the urine, the belly-ache, hot and dry in the third degree — and then sets two peer-reviewed studies beside it for the parts the 1615 book could not know: the Mexican and Guatemalan native range, the sixteenth-century passage to Europe out of Mexico, the two common names of which only one is geographically true, and the seven thousand hectares now grown for xanthophylls. It also says plainly which popular claims about the flower it cannot support from the sources it has read.
Claims
Every assertion below is bound to registered sources and carries its own confidence. Weight them; do not treat the page as uniformly authoritative.
The plant has a chapter of its own in the Mexican imprint of 1615 in which fray Francisco Ximénez put Francisco Hernández's Latin survey of the natural history of New Spain into Spanish. In libro segundo it is "CAP. LV. DE LA LLAMADA CEMPOALxochitl, yerua", and the description is of a plant recorded under its Nahuatl name, not under a European one: leaves like chicory's, "espinossas y aserradas, y asperas", stalks a span long and yellow, ending in flowers "à manera de fluecos", and a root resembling a radish in shape and size.
What the book records is a medicine rather than an ornament or a ritual flower. The decoction of the root is bitter, and "aplicado en melezina heuacua el viẽtre, proboca le orina, quita el dolor de barriga, por q̃ es aguda y de sutiles partes", the plant being classed as hot and dry in the third degree. Ximénez's book was compiled explicitly for "los que viuen en estancias y minas, do no ay Medico ni Botica", so the entry is a working prescription for people beyond the reach of a pharmacy, not a herbarium note.
Modern botanical literature agrees on the origin and dates the transfer to the century of that survey. A 2021 phytochemical study of Tagetes erecta states that the species is "native to Central America (especially Guatemala and Mexico)" and that "it was introduced to Europe in the 16th century, having been brought from Mexico". The plant that Hernández's collectors were describing in New Spain was moving to European gardens in the same decades.
The names it acquired on the way are a case study in how origin gets lost. A 2018 study of the same species records that it "is commonly known as 'African marigold' or 'Aztec marigold'" and is "a flowered annual herbaceous plant native from Mexico" — two names in circulation for one plant, only one of them right about where it grew wild. The 2021 study adds the Spanish and Portuguese "flor de muerto" and "cravo de defuntos", which it connects to "the common practice in Central America of using an aqueous extract of the plant for washing bodies after death".
The scale of the modern crop is the measure of what the transfer was worth, and it is agricultural rather than medicinal. The 2021 study estimates that "over 7000 ha are used worldwide for the cultivation of this species, each plant being able to provide around 330 mg xanthophylls"; the 2018 study says the species "is widely cultivated for ornamental, poultry, and medicinal purposes", that its flowers serve "as an ingredient in salads and as natural food colorant", and that most research on it has concentrated on the xanthophyll content "and its use as antioxidant for prevention of age-related macular degeneration". The Mexican flower is now the world's raw material for lutein.
Where the sources do not reach, and where this object stops. The 1615 chapter gives no ritual or funerary use and no pre-Hispanic context; neither modern study documents the Nahuatl etymology, the Day of the Dead observances now inseparable from the flower in Mexico, or any pre-Columbian record of cultivation, and the 2021 study's inference from "flor de muerto" to body-washing is offered without a primary citation. The claim made here is narrow: a plant recorded under a Nahua name in a Mexican book of 1615 as a medicine, carried to Europe in that century, and turned into a global industrial crop — not a claim about what the Mexica did with it, which would need Sahagún and the archaeobotanical literature this corpus has not opened.