Tacaquirensis
$90.00
Grouping
The rest of the genus
The largest group in this library, and deliberately so. These are the names our sources place in Trichocereus without placing them under pachanoi, bridgesii, peruvianus or scopulicola — plus every name where the sources simply stop before the species.
492 names in the library22 in the yard2 for sale now
Worth knowing
A name landing here is not a judgement about the plant. It means the record does not support a narrower answer, and putting one there anyway is the thing this library exists not to do.
Every feature on this page moves with age, sun and water: a thirsty plant in hard light grows longer spines and a heavier bloom than the same clone in the shade. None of it settles an identity on its own, a clone name is not proof of a species, and a photograph is a pointer rather than an answer.
On the shelf now
Growing here
The mother plants this yard cuts from, in this group.
Names in the library
Every one of these carries a seal drawn from what a source actually recorded about it — the ribs, the spines, the growth form. A plain ring means nobody has written that one down yet.
The others
Sources
How this hub was written
Nothing here is copied. Every page was written from a fact list I built by reading, watching and cross-checking the sources below, with each fact tagged to where it came from. I keep that fact-by-fact record on my side of the counter; what you read here is what held up after checking it against my own plants.
The community wiki, written by many growers and published under a Creative Commons BY-NC 4.0 licence. We use its facts and reproduce none of its text or pictures.
@sanpedromastery6262 on YouTube
A hobby grower filming the same collection through two very different climates, which is where a lot of our seasonal numbers come from.
A one-person nursery in San Diego County filming its own practice in the open, in a climate close to this one.
Where growers argue things out in public. Useful for what actually goes wrong, and for seeing where opinion is split.
A Southern California nursery whose buyer guides and posted policies are the clearest record I found of what a cutting in the post should be like. They are also a competitor, and I read them as one.
And checked against
Growers know things nobody has written down, and those five are where that knowledge lives. But anything that can be checked against somebody who publishes under their own name and answers for it has been.
University of Arizona Cooperative Extension
A land-grant university's extension service, on sunburn and acclimation, freeze damage, planting depth, drainage, over-watering, rot and pests. Where this site and a forum disagree about water, this is the tiebreaker.
The Royal Horticultural Society
A national horticultural society's own growing guide: the watering year, the cool dry winter rest, mixes, pot size and how long a cut takes to callus.
A botanical garden's pest advice, written for cacti and succulents specifically — what mealybugs, scale, spider mites and root mealybugs look like, and what actually shifts them.
The International Plant Names Index
Kept jointly by Kew, the Harvard University Herbaria and the Australian National Herbarium. It is where the species names on this site were checked against the record of what has actually been published, and by whom.
Haseltonia, the yearbook of the Cactus and Succulent Society of America
Peer-reviewed taxonomy. The argument about macrogonus, pachanoi and peruvianus is settled in papers like this one, not in a comment thread, and this is the paper that made the change.
Nine more sit behind these pages the same way — extension horticulture from Illinois, South Carolina and two California counties, the Caryophyllales Network, the Desert Botanical Garden, a society’s grafting article and a journal paper on the family tree. Every one of them, and how much of this site rests on each, is on the sources page.
Every photograph on this site is of a plant grown in this yard — nobody else’s. The teaching pictures are drawings rather than photographs: a drawing can label the one thing it is teaching, hold two plants in the same light, and leave out everything that would only distract. And I will not tell you what your cactus is from a photograph: light, age and water change every feature people identify these plants by, so a photo is a hint and never a verdict.
Written from scratch off a cited fact list, never copied. Learned from the sanpedrocact.us community wiki (CC BY-NC 4.0), @sanpedromastery6262 and @IMDAVESBUD on YouTube, r/sanpedrocactus and medicactus.com's buyer guides, then checked against university extension horticulture, botanical gardens, cactus and succulent societies and the published botanical record. I will not name a plant from a photograph.
Every source behind this site →