Plate 1 figs. a–e · 3 observations
This species has been photographed under an open licence only 3 times, so some figures below are different views of the same plant, taken on the same day, rather than different individuals. They are usually different parts of it: the leaf, the flower, the bark.
Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.
Where it actually grows measured, from 31 observations
| Condition | 5th percentile | Median | 95th percentile |
|---|---|---|---|
| Coldest month, mean daily low | 1.8 °C | 5.3 °C | 8.7 °C |
| Warmest month, mean daily high | 18.7 °C | 20.4 °C | 22.6 °C |
| Annual rainfall | 109 mm | 290 mm | 869 mm |
| Rainfall in the driest quarter | 4 mm | 9 mm | 28 mm |
It is found where winters are cool but frost is light or absent. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 31 research-grade observations of Armatocereus riomajensis that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.
This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.
Sourcesevery claim on this page
- World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
- iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite. It has no native range either: Kew's checklist does not cover this taxon.