Lemon Ball Cactus
Mammillaria rhodantha subsp. pringlei
mam-mil-AR-ee-uh rho-dan-the PRING-lee-eye
Cactus pringlei J.M.Coult.
Neomammillaria pringlei (J.M. Coult.) Britton & Rose
According to Plants of the World Online by Kew and Tropicos, Mammillaria pringlei (J.M.Coult.) K.Brandegee is the accepted and correct name of this species of Mammillaria. It was named and described by Mary Katherine Brandegee in Zoe in 1900. It was first named and described as Cactus pringlei by John Merle Coulter in Contributions from the United States National Herbarium (Smithsonian Institution) in 1894.
Although Plants of the World Online by Kew says Mammillaria pringlei is the accepted scientific name, many other databases are saying the name is still Mammillaria rhodantha subsp. pringlei. Plants of the World Online list both Mammillaria pringlei and M. rhodantha as accepted species and list no accepted infraspecific names for either one. However, they do list Mammillaria rhodantha subsp. pringlei as a synonym of Mammillaria pringlei. Many plant name databases only update periodically or do bulk updates but maybe not that often. Many databases are also still using The Plant List as a source for their information. Well, The Plant List is no longer maintained and has not been since version 1.1 in 2013. Plants of the World Online was launched by Kew in 2017, and while still a work in progress, it is probably more up-to-date than most other databases. Currently, Kew is also in control of The Plant List but have made no updates. The editor informed me they may in the future. Even though Plants of the World Online is new and is trying to make correct updates as they go along and as names change, I am sure it is hard to keep up sometimes. While many names have been the same for a very long time, others have changed multiple times. Many plants also still have multiple scientific names.
According to several other databases, Mammillaria rhodantha subsp. pringlei J.M.Coult.) D.R.Hunt is the correct and accepted scientific infraspecific name for this subspecies of Mammillaria rhodantha. It was named and described by David Richard Hunt in Mammillaria Postscripts in 1997.
While my Mammillaria pringlei and Mammillaria rhodantha do have a lot in common, their spines are different colors. However, Mammillaria rhodantha is apparently a variable species and doesn’t necessarily have to have reddish-brown spines. Spine count also plays a roll in determining the correct species… You can click on the links below to get more information.
Whether you call this plant Mammillaria pringlei or Mammillaria rhodantha subsp. pringlei, it is a great cactus and one well worth growing. You can call it by either name because there are no rules as to which name you choose to use. Many times when a plant has multiple scientific names within the same genera, the name applied first becomes the accepted name and the rest are synonyms. In that case, Mammillaria pringlei would be the accepted name.
This species was also named Neomammillaria pringlei (J.M.Coult) Brittan & Rose. It was named and described as such by Nathaniel Lord Britton and Joseph Nelson Rose in The Cactaceae in 1923. Neomammillaria is now a synonym of Mammillaria.
I bought this cactus from Lowe’s on April 24, 2017. The label says:
“Mammillaria pringlei, native to Mexico, is sometimes considered a subspecies of Mammillaria rhodantha. The stem is covered in dense, golden spines, sometimes curling to lengths of 1” or more. Rings of deep flowers appear in summer. Protect from frost.”
When I did my initial research back in April 2017, all the websites I checked with agreed that Mammillaria pringlei was, in fact, a synonym of Mammillaria rhodantha subsp. pringlei. With that in mind…
The new Plants of the World Online by Kew lists Mammillaria pringlei (J.M.Coult.) K.Brandegee as the accepted name based on Mary Katherine Brandegee’ description in Zoe in 1900. They say Mammillaria rhodantha subsp. pringlei is a synonym of Mammillaria pringlei. Currently, Plants of the World Online is the most up-to-date plant database and Mr. Goverts, the editor, is pretty much on top of his game
The 2013 version of The Plant List (no longer maintained), Llifle (Encyclopedia of Living Forms, Dave’s Garden, CactusGuide, GRIN (U.S. National Plant Germplasm System) all say Mammillaria rhodantha subsp. pringlei is correct. Many databases were using The Plant List as a reference and haven’t started following Plants of the World Online yet. The Plant List has not been updated since 2013 and Kew has taken it over and is replacing it with Plants of the World Online. At some point, they may update The Plant List again.
This is just one of a few everyone doesn’t agree on and I am not going to choose sides here. I am just a gardener and small plant collector with a blog. I like this cactus no matter what it’s “official” name is.
Isn’t it neat how many cactus species flowers grow in a circle around the top of the plant?
Zones: USDA Zones 9b-11 (25 to 40° F)
Light: Sun to part shade
Soil: Fast-draining. Potting soil amended with grit and pumice or perlite.
Water: Average during the growing period, barely to none during the winter.
The IUCN Red List of Threatened Species list Mammillaria pringlei, or whatever its name is, as vulnerable in its natural habitat. This is due to its restricted range, being present in only three areas. Information states it has experienced declines because of the collection of its flowers and even whole plants for Christmas decorations. Apparently, this species is not found in any of the protected areas.
Temps were starting to get cooler and would soon be time to bring the potted plants inside for the winter.
I measure the cacti periodically to see their rate of growth. Some grow so SSSSLLLLOOOOWWWW you need to measure them to make sure they are alive. Well, seriously, if they were dead they would turn brown and shrivel up. When I moved the plants inside for the winter, this cactus measured 4 1/2″ tall x 3 1/2″ wide and it is in a 3 1/2″ tall and wide pot. I measured it when I bought it, but somehow I can’t find where I wrote it down… I will find it someday.
When you bring your plants inside for the winter, make sure you clean off your pots. Sometimes spiders build webs under the rims and will be crawling around in your house. I kind of like those little black, fuzzy spiders so I leave their nests alone. You should remove any dead leaves from trees, grass, twigs, etc. from your pots. Always check for insects that may be trying to hibernate around the base of your plants.
I usually have a colony of ants hibernating in one of my pots which I usually find when I water. The ants swarm out then go back in when the soil is dry again. Sometimes they move to another pot, eggs and all.
Cactus and succulents are not hard to grow if you follow a few basic rules. I have a page called Cactus & Succulent Tips you can check out if you like.
I put this cactus on the kitchen windowsill for the winter with a few others. It gets morning sun and is doing very well there.
This species is one of many fast growing cactus. Many, like this one, freely flower even at a young age which just adds more interest. I am not sure how many there are, but the top is LOADED with buds. It is so funny how long it takes for them to actually flower, though.
When warmer temperatures finally arrived I was able to take the plants back outside. (Ignore the plant to the right).
On June 24, in the late afternoon, I noticed the buds on the Mammillaria pringlei were getting larger…
Then on June 28, I was out earlier and some of the flowers were opened.
It is very interesting how its flowers are arranged in a circle around the top of the plant.
Later on, in the early evening, the flowers were closed up. They kind of look like tiny tulips.
I will continue adding more photos and information as time goes by. Be sure to check out the links below for additional information about the genus, species and growing information. The links take you directly to information about the genus and species. There are many online sources for this species as it is very popular.
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. 🙂