French oregano

What it is

Coleus amboinicus Lour. is a semi-succulent perennial of the mint family, with fleshy stems and broad oval leaves. Its aroma is pungent and oregano-like with thyme notes, and its essential oil is mainly thymol and carvacrol, in proportions that vary with the sample. The leaves are the part used.

Kew accepts Coleus amboinicus and lists Plectranthus amboinicus (Lour.) Spreng. as a homotypic synonym. Cuban agronomy papers still use the Plectranthus name, and one title spells it Plecthranthus. English names include Cuban oregano and Indian borage; Kew records the species as introduced in Cuba.

Names and the oregano problem

The 1998 Cuban technical article calls the plant orégano, orégano francés and orégano de la tierra. The RHS profile gives Cuban oregano. These are the sources' own labels. They do not make the plant Origanum vulgare, Lippia micromera or Ocimum gratissimum, which appear in other oregano-related Cuban sources. A name that sounds like oregano is not an identification.

As a seasoning in Cuba

A 2007 Cuban national report on plant genetic resources lists Plectranthus amboinicus, under the name Oregano, as a condiment in an urban-agriculture inventory. The entry records the plant as a condiment, not how common that use was.

A 1998 technical article describes the plant as grown in patios and family gardens in Cuba, with a strong characteristic aroma. It does not name the plant part used, a dish, a quantity or a preparation. A 2010 thesis from Pinar del Río treats the plant as a medicinal crop.

Cultivation and drying evidence

The 2010 thesis tested terminal cuttings in nursery beds in Pinar del Río over 45 days, on alluvial sandy loam, for medicinal propagation. The thesis has inconsistencies in its fresh and dry foliage measures, so no corrected value or fertilizer recommendation is drawn from it. A 2022 paper hand-harvested leaves from open-sky 1 by 1 m polystyrene beds at INIFAT nine months after establishment and reports no yield, spacing, irrigation comparison or harvest interval.

The same 2022 paper measured moisture sorption in dried leaves in the laboratory at 27 ± 2 °C and interprets a moisture range of 5 to 13 percent for storage under Cuban conditions. That is a laboratory interpretation, not a validated drying endpoint, microbial challenge or shelf-life test. The RHS gives UK guidance for growing under glass and outdoors with an H1B hardiness rating from a UK scheme, which is not a measured frost limit for Cuba.

What the sources leave open

No Cuban recipe or measured household method was found: the inventory and the abstract say condiment and give no dish, ingredient list, amount, steps, yield or storage. None of the records documents a microbial culture, a fermentation role or a preservative effect. No Cuban frost trial, pest survey, container trial or greenhouse study was located, and introduced status in Kew does not establish invasiveness or conservation status. Smell does not establish that dried leaf is safe to keep. The full 1998 article and a 2008 intercropping paper were seen as abstracts only.