Gray Ghost, Organ Pipe, Pitayo de Octubre (of October), Pitaya
Synonyms of Stenocereus pruinosus: Cactus pruinosus Monv. ex Steud., Cereus laevigatus Salm-Dyck, Cereus pruinosus (Otto ex Pfeiff.) C.F.Först., Cereus roridus Pfeiff., Echinocactus pruinosus Otto ex Pfeiff., Griseocactus pruinosus (Otto ex Pfeiff.) Guiggi, Griseocereus pruinosus (Otto ex Pfeiff.) Guiggi, Lemaireocereus laevigatus (Salm-Dyck) Borg, Lemaireocereus pruinosus (Otto ex Pfeiff.) Britton & Rose, Lemaireocereus schumannii (Mathsson ex K.Schum.) Britton & Rose, Neogriseocereus pruinosus (Otto ex Pfeiff.) Guiggi, Pachycereus schumannii (Mathsson ex K.Schum.) C.Nelson, Rathbunia laevigata (Salm-Dyck) P.V.Heath, Rathbunia laevigata var. schumannii (Mathsson ex K.Schum.) P.V.Heath, Rathbunia pruinosa (Otto ex Pfeiff.) P.V.Heath, Ritterocereus laevigatus (Salm-Dyck) Backeb., Ritterocereus pruinosus (Otto ex Pfeiff.) Backeb., Stenocereus laevigatus (Salm-Dyck) Buxb.
Stenocereus pruinosus (Otto ex Pfeiff.) Buxb. is the correct and accepted scientific name for this cactus. It was described by this name by Franz Buxbaum in Botanische Studien in 1961. It was first named and described as Echinocactus pruinosus by Christoph Friedrich Otto and Louis (Ludwig) Karl George Pfeiffer in Enumeratio Diagnostica Cactearum in 1837.
The genus, Stenocereus (A.Berger) Riccob., was named by Vincenzo Riccobono and first mentioned in Bollettino delle Reale Orto Botanico di Palermo in 1909. It replaces Cereus subsp. Stenocereus which was named by Alwin Berger and first mentioned in the Annual Report of the Missouri Botanical Garden in 1905. Plants of the World Online by Kew currently list 21 accepted species in the Stenocereus genus (as of 1-6-20 when I am updating this page). Those numbers could change.
I brought my Stenocereus pruinosus home from Wal-Mart on 2-1-16. It was growing in a 2 1/2” (4 oz.) pot and it measured approximately 2 7/8” tall x 2 3/4” wide at the time. The label states:
“Lemaireocereus pruinosus is a powdery, gray columnar cactus that grows to 20’ in height in time. White nocturnal flower. Native habitat is Puebla, Mexico. Protect from frost. Provide bright light/sun; hardy to 32 degrees F.; to 6’ tall. Water thoroughly when soil is dry.”
Stenocereus grows in tropical deciduous forests in Oaxaca, Puebla, and Veracruz, Mexico and is cultivated for its edible fruit. Stenocereus pruinosus is tree-like or columnar cactus that can grow 12-15 feet tall with one or more trunks.
When I brought my plant in for the winter on October 17, 2017, the Stenocereus pruinosus measured 3 3/4″ tall x 2 3/4″ wide.
Zones: USDA Zones 9b-11(25 to 40° F)
Light: Sun to light shade
*Soil: Well-drained. Potting soil amended with pumice or perlite and grit.
Water: Average during the summer months, barely during the winter.
*There are many cactus and succulent recipes online. I used 2 parts Miracle Grow or Schultz potting soil with 1 part additional perlite and 1 part chicken grit for many years. Many cactus and succulent enthusiasts recommend using pumice in place of perlite and grit. I began using a mixture of about 50/50 Miracle Grow Potting Soil and pumice in the Fall of 2018 with favorable results. I repot any time of the year as necessary but I have found that repotting in the fall keeps their soil nice and loose for the winter.
Doing very well inside for the winter, the Stenocereus pruinosus is snuggled with many other cactus and succulents on a table in the bedroom. They are getting lots of good sun from a south-facing window.
Back outside again for the summer…
After the Japanese Beetle invasion, I moved the potted plants, cactus, and succulents to the front and back porch of the house. The Stenocereus pruinosus is enjoying its summer in the sun on the back porch.
I had to move the potted plants inside for the winter on October 10 because the forecast was calling for an “F” in a few days and the nighttime temperatures were getting cooler. The Stenocereus pruinosus measured 3 7/8″ tall x 3″ wide but I forgot to take its photo
November 29 was a nice spring-like day, so I took the cactus to the back porch for a photoshoot. I was working on a post to show the difference between the cactus in my collection.
Stenocereus pruinosus is a very interesting plant for sure. Its areoles produce 1-4 short and stout central spines. Llifle also says they have 5-8 radial spines but mine has none. The Stenocereus pruinosus in my collection has five ribs but some specimens have more. They produce side branches from the base which give them a V-shaped appearance.
All the plants made it through the winter and were glad to be outside for the summer. I put the Stenocereus pruinosus and most of the other cactus on the back porch.
I was fairly busy over the summer so I didn’t take a lot of photos of the potted plants. They all did very well despite a little neglect.
I had to move the potted plants inside for the winter on October 11 because an “F” was in the forecast. I always take photos of the plants when I move them inside and measure the cactus and some of the succulents. The Stenocereus pruinosus measured 4 3/4″ tall x 2 3/4″ wide. That’s pretty good considering it was only 2 7/8″ tall when I brought it home on February 1, 2016.
I have enjoyed having the Stenocereus pruinosus as a companion and it is much different than the others I have grown. I like the silver color and the way it gets darker with more light. There is also a variegated variety of this cactus which would also be very interesting.
I hope you enjoyed this page and maybe found it useful. If you have any comments, questions or suggestions, I would like to hear from you. Please click on “like” if you visited this page. It helps us bloggers stay motivated. 🙂 You can check out the links below for further reading. The links take you directly to the genus and species of this plant.