A constellation
on each rib.
I found this Onzuka at Verde in Scena in Rome in 2026, at La Casa dei Cactus. What drew me in was its changing field of pale flecks—no two ribs quite tell the same pattern.
Onzuka is a cultivated form of Astrophytum myriostigma, not a wild species. Its white flecking can gather into dots, short lines and larger islands across the green ribs. I like the way the pattern changes as the body turns: from a distance it reads as an even silvering; up close it breaks into separate marks. This is the detail I want to follow in this plant as it grows.
The name reaches back further than the specimens in this collection. An archived account places the emergence of Onzuka’s white-flecked line in Japan around 1974–77. It describes cactus grower Tsutomu Onzuka making repeated crosses and backcrosses with A. myriostigma and its nudum form; some seedlings developed an unusually dense white pattern. The account says commercial sales began in 1979. A separate 2015 article gives a similar mid-1970s date and describes the result as an unexpected outcome of that breeding work. These sources give us a likely period and a grower associated with the line, not a precise date for one original plant or a definitive account of every parent.
The cultivar’s Japanese history and the species’ wild range are different stories. Kew records A. myriostigma as a species of northeastern Mexico, first published by Charles Lemaire in 1839. Field records place it across dry parts of northern and central Mexico, including Coahuila, Nuevo León, San Luis Potosí and Tamaulipas. Those are species-level records; they do not establish where this cultivated Onzuka—or its seed line—originated before it reached the nursery.
This plant joined my collection in 2026, when I bought it from La Casa dei Cactus at Verde in Scena in Rome. Its earlier grower and provenance were not recorded. The passport keeps that distinction clear: a Japanese cultivar history for the name, and a Rome acquisition record for this individual.
Research trail
- The Onzuka Cactus Plant · historical account — dates the line to around 1974–77, associates it with Tsutomu Onzuka, and reports commercial sales from 1979.
- Stirling Baker · “A constellation of Astrophytum” (2015) — independent account of the Onzuka line and its breeding history.
- LOVEGREEN · 恩塚鸞鳳玉 — Japanese-language horticultural overview of the cultivar’s appearance and attribution.
- Kew · Plants of the World Online — accepted species name, publication and range.
- USDA GRIN · Astrophytum myriostigma — state-level distribution records in northern Mexico.
