The definitive source for rare cactus collectors
Encyclopedic care guides, species profiles, field number collector logs and everything else you’ll need to know about taking care of your collection.
Field number database
Wild-collection provenance for rare cacti, searchable by collector code, species, or locality.
↳ 59,794 records · 280 collectors · 10,393 GPS points · updated quarterly
A cactus collector field-number database is a tool used to identify wild specimens by searching for collector acronyms and field numbers. For example, FR 207 is Friedrich Ritter's number for a Copiapoa cinerea he collected at Taltal, Chile in June 1954. Each record traces the plant back to where it was collected (locality), the date collected, and the collector's name, acting as a "birth certificate" for the specimen.
Data and comparison tools
Charted from primary sources and free to download. Every figure traces to a paper, a state report or a live database.
Peyote trade and harvest data, 1986 to 2016
Thirty-one years of Texas distributor reports beside the regrowth study that explains them.
2,317,380 buttons at the 1997 peak, 867,674 in 2016, a 63% decrease
Where peyote grows
Fifty-one county and municipio markers for the genus, an elevation profile, and why no marker is a GPS pin.
8 Texas counties, 7 Mexican states, 42 of 51 markers L. williamsii
Lophophora species compared
Four accepted species side by side, an identification key, and every published alkaloid measurement.
4 species, 26 alkaloid measurements, all on CITES Appendix II
Editor’s Picks
The 12 Best Places in the World to See Rare Cacti
From the Tehuacan-Cuicatlan biosphere reserve and the fog-fed Atacama to the Huntington Desert Garden and the Princess of Wales Conservatory,... Culture20 min read
Top 10 Universities for Botany and Plant Biology in the United States
Ranked list of the 10 best U.S. universities for botany and plant biology, evaluated on herbarium depth, greenhouse facilities, faculty... Research16 min read
Is Peyote Legal? US States and Around the World (2026)
Peyote (Lophophora williamsii) is a federally Schedule I plant in the United States with a narrow Native American Church religious-use... Legality38 min read
The Best Cactus and Succulent Collections to Visit in the United States
The Huntington Library cactus garden, Desert Botanical Garden Phoenix, Boyce Thompson Arboretum, and five more US institutions where serious rare-cactus... Collecting12 min read
San Pedro Cactus (Trichocereus pachanoi): The Collector’s Complete Botanical Guide
San Pedro cactus is Trichocereus pachanoi, a fast-growing Andean columnar cactus from Ecuador and Peru at 2,000-3,300 m. Taxonomy, habitat,... Field Guide11 min read
Most Expensive Cacti Ever Sold: How Mature Cultivated Copiapoa Reach $15,000+
Mature seed grown Copiapoa cinerea of 30+ years cultivation routinely clear $10,000 to $15,000 and beyond in the specialist collector... Rankings14 min readRecent Articles
Is It Legal to Own San Pedro? A State-by-State Guide
Owning San Pedro cactus as an ornamental is generally legal across the United States. Mescaline, the alkaloid the plant contains, is Schedule I under the federal Controlled Substances... Legality25 min read · Apr 20, 2026
Rare Cactus of West Texas & Big Bend: A Field Guide
Which cacti grow in Big Bend and the Trans-Pecos, when they bloom, the law on collecting, and how to see... Field Guide11 min read
Why Miracle-Gro Cactus Soil Kills Rare Cacti (And What Collectors Use Instead)
Miracle-Gro Cactus, Palm and Citrus soil kills rare cacti because the bag is 70-80% peat moss, perlite, and bark fines.... Plant Care9 min read
Cactus Taxonomy: How Habitat Photography Reclassified Species
Field photographs reshaped Copiapoa, Ariocarpus, and Aztekium taxonomy through the late twentieth century. How named photographer-taxonomists drove lumping, splitting, and... Research16 min read
Early Signs of Mealybugs: Catch Them Before the Outbreak
The early signs of mealybugs are white cottony flecks in sheltered crevices, sticky honeydew, and ants working the plant. How... Plant Care22 min readThe rarity index
Inside the rarity index
Not all rare cacti are equally rare. Our list of the rarest cactus plants in the world ranks specimens by wild population, cultivation difficulty, and trade availability.