Mammillaria vetula subsp. gracilis
mam-mil-AR-ee-uh VET-uh-luh GRASS-il-is
Mammillaria gracilis var. fragilis
mam-mil-AR-ee-uh GRASS-il-is FRAJ-ih-liss
I brought this Thimble Cactus home with me from Lowe’s on April 20, 2013. The label said it was a Mammillaria gracilis fragilis… Upon research, I found out the name had changed.
Other synonyms of Mammillaria vetula subsp. gracilis from Plats of the World Online (21): Cactus pulchellus (Salm-Dyck) Kuntze, Cactus regius (C.Ehrenb.) Kuntze, Cactus vetulus (Mart.) Kuntze, Chilita fragilis (Salm-Dyck ex K.Brandegee) Orcutt, Chilita vetula (Mart.) Orcutt, Escobariopsis gracilis (Pfeiff.) Doweld, Escobariopsis vetula (Mart.) Doweld, Krainzia gracilis (Pfeiff.) Doweld, Mammillaria fragilis Salm-Dyck ex K.Brandegee, Mammillaria gracilis Pfeiff., Mammillaria gracilis var. fragilis A.Berger, Mammillaria gracilis var. pulchella (Salm-Dyck) Salm-Dyck, Mammillaria kuentziana P.Fearn & B.Fearn, Mammillaria magneticola J.Meyrán, Mammillaria pulchella Salm-Dyck, Mammillaria regia C.Ehrenb., Mammillaria vetula subsp. gracilis (Pfeiff.) D.R.Hunt, Mammillaria vetula subsp. lacostei Plein & Heinr.Weber, Mammillaria vetula subsp. magneticola (J.Meyrán) U.Guzmán, Neomammillaria fragilis (Salm-Dyck ex K.Brandegee) Britton & Rose, Neomammillaria vetula (Mart.) Britton & Rose
Mammillaria vetula subsp. gracilis (Pfeiff.) D.R.Hunt is the correct and accepted infraspecific name for this cactus. It was named and described by David Richard Hunt in Mammillaria Postscripts in 1997. It was first named Mammillaria gracilis Pfeiff. by Ludwig Karl Georg Pfeiffer in Gartenzeitung in 1838.
Mammillaria gracilis var. fragilis A.Berger was named and described by Alwin Berger in Kakteen in 1929.
Mammillaria vetula Mart. was named and described by Carl (Karl) Friedrich Philipp von Martius in Nova Acta Physico in 1832.
There are other synonyms in a roundabout way, one way or another, but you can check out the links below for more about them.
Plants of the World Online says Mammillaria vetula subsp. gracilis is a synonym of Mammillaria vetula. OK, so I goofed on purpose. Well, Plants of the World Online is a fairly new site and they are still uploading data. Perhaps they haven’t figured out that Mammillaria vetula subsp. gracilis should be an infraspecific name. It is accepted on Llifle, Dave’s Garden, and CactusGuide…
This was my first Mammillaria so I was anxious to see how we got along. When temps warmed up enough I moved this cactus outside with the rest of the plants then I put it in a larger pot.
Zones: USDA Zones 9a-11 (20 to° F)
Size: 6” or so tall
Light: Sun to part shade
*Soil: Fast-draining. Potting soil amended pumice or perlite and grit
Water: Average during the growing period, barely in winter
Flowers: Pale to bright yellow
*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.
The Thimble Cactus is a very easy plant to grow if you follow a few simple rules. They don’t mind regular watering during the summer months, but to much water in the winter is NOT a good idea. I just water my cactus maybe once or twice during the winter if at all. When I water my cactus and succulents during the summer, I just go over them with the wand one time. The other plant’s pots get filled to the rim.
Information online says that this plant does well in full sun to part shade. When you move your plants outside for the summer, they need to get used to more light gradually. I normally place mine in light to part shade at first then gradually slide them over on the table to get more light. If they show any sign of burn, I put them back in more shade. I think I kept this cactus on the table behind the shed in more shade all summer.
Once in a while I will notice one of the balls of thorns has fallen off on the table. I just put it back in the pot where it can take root. That is actually how they spread in the wild.
We made it through the 2013-2014 winter just fine and it was glad to be back outside again.
I really enjoyed this plant as a companion, but unfortunately, I gave up most of my plants after the above photo was taken. I am back collecting plants again, so maybe someday I will bring home another Mammillaria vetula subsp. gracilis.
I found this cactus at Wagler’s Greenhouse when I took plants there in September. It was unlabeled but I was sure it was a Mammillaria. I wasn’t sure what species it was at first because I was used to seeing them sold in clusters and not as a single specimen.
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. I usually measure the cactus and succulents when I bring them inside. This plant measured 2 1/4″ tall.
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.
The species, Mammillaria vetula, has 1-2 central spines and at least 25 radial spines. The subspecies often lacks the central spines and only have 11-16 radial spines.
The potted plants made it through the winter and once evening temperatures warmed up I moved the potted plants back outside for the summer. I moved the cactus to the back porch where they could receive full sun. The Mammillaria vetula subsp. gracilis had grown lots of offsets.
I was fairly busy during the summer so I didn’t take many photos. All the plants did very well despite a little neglect.
I had to bring the potted plants inside on October 11 because an “F” was in the forecast. I always take photos of the plants as I bring them inside and measure the cactus and some of the succulents but I forgot to photograph this one so I did it on the 13th. It measures 2″ tall and most of its offsets have fallen off.
I was surprised to see a couple of buds on this cactus on 11-23-19.
This particular cactus will be interesting to watch grow because it started out as a single plant and I will get to watch it multiply. I just have to keep an eye on the offsets when they fall off to make sure they don’t blow away or fall offon the ground during the summer.
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. They take you directly to information about the species.