Mammillaria plumosa-Feather Cactus

Mammillaria plumosa (Feather Cactus) after I put it in a pot on 9-22-18.

Feather Cactus

Mammillaria plumosa

mam-mil-AR-ee-uh  plum-OH-suh

Royal Horticultural Society’s Award of Garden Merit

Synonyms of Mammillaria plumosa from Plants of the World Online (4) (Unchanged as of 11-13-20): Chilita plumosa (F.A.C.Weber) Orcutt, Ebnerella plumosa (F.A.C.Weber) Buxb., Escobariopsis plumosa (F.A.C.Weber) Doweld, Neomammillaria plumosa (F.A.C.Weber) Britton & Rose

Mammillaria plumosa F.A.C.Weber is the correct and accepted scientific name for this species of cactus. It was named and described by Frédéric Albert Constantin Weber in Dictionnaire d’Horticulture in 1898. 

The genus, Mammillaria Haw., was named and described by Adrian Hardy Haworth in Synopsis Plantarum Succulentarum in 1812.

Plants of the World Online by Kew lists 164 accepted species in the Mammillaria genus (as of when I am updating this page on 12-13-20). It is a member of the plant family Cactaceae with 144 genera. Those numbers could change as updates are made.

THERE ARE SEVERAL LINKS AND GROWING RECOMMENDATIONS AT THE BOTTOM OF THE PAGE FOR FURTHER READING.

Mammillaria plumosa after I unwrapped it from being shipped on 9-22-18, #511-4.

I bought this plant from a seller on Ebay and it arrived on September 22 (2018). It was really NICE and arrived safe and sound wrapped in toilet paper. The selection on Ebay and a few groups on Facebook is much better than what I can find at Wal-Mart and Lowe’s…

Mammillaria plumosa with its roots on 9-22-18, #511-6.

The cluster measured approximately 3/4” tall x 2 1/4” wide. I couldn’t tell how many offsets are in the cluster because of all the fuzz. A single specimen of this species can take a couple of years to offset, but I can feel there are several in this cluster of fuzz. It kind of reminds me of a VERY HAIRY Thimble Cactus (Mammillaria vetula subsp. gracilis).

Mammillaria plumosa on 9-22-18, #511-7.

Mammillaria plumosa is native to Coahuila and Nuevo León in Mexico where it grows on limestone cliffs in sparse shrubland at an elevation of about 2,400 to 4,500 feet (730 to 1,350 meters) above sea level. 

Its status in its natural habit is listed as “near threatened” by the IUCN Red List mainly due to illegal collection for trade. Locals also collect and sell the plants at local markets during Christmas because they are used to decorate nativity scenes. 

Mammillaria plumosa in its new pot on 9-22-18, #511-10.

I put the cluster in the smallest pot I thought it should be in for its size. Cactus do not need large pots because their root system is not that big. Too much soil under the plant can lead to root rot, which is another reason not to overwater.

Mammillaria plumosa on 11-29-18, #534-23.

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.

This cluster of plants has one central plant 1 1/2 to 1 3/4″, depending on where you measure, with six offsets.

Mammillaria plumosa is a clumping species that forms dense mounds about 1 1/2 to 3” tall and up to 15” wide completely covered with feathery spines. 

Mammillaria plumosa close-up on 12-1-18, #535-18.

The areoles on its small, flattened tubercles produce about 40 radial spines that are feathery and interlacing. The spines themselves produce hairs along their axis which makes them resemble a bird’s feathers. Mauseth Research says, “Epidermis cells on spines of Mammillaria plumosa grow out as trichomes, shading the plant.” This species has no central spines.

Llifle (Encyclopedia of Living Forms) says, “The spines in this species have very long hairs along the spine-axis arranged as are the segments of a bird’s feather and that furnish an epidermal protection against the blasting sun of the desert.”

I looked at the plant closely with a magnifying glass and it was still fairly difficult to see what is going on because everything is so small. The tubercles are fairly close together so the radial spines kind of interlace with each other. The radial spines, even though Llifle says they are 1-7 mm long, some of them measured 1/8″ long and are pretty stiff. Even though they are thin and stringy looking, they are more like a very thin wire. Very few resemble feathers, BUT if you look closely at the above photo you can actually see a few in this photo that do look like feathers… The wooliest areas are around the apex and feel like cotton. Oh yeah… The brown spots in the photo are the centers of the areoles. It is going to be neat watching this plant grow.

By the time I was finished looking the plant over, it was telling me, “ENOUGH ALREADY!”

<<<<2019>>>>

Mammillaria plumosa on 6-22-19, #593-32.

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.

I was fairly busy during the summer so I didn’t take many photos. All the plants did very well despite a little neglect.

Mammillaria plumosa at 1 1/2″ tall x 3″ wide on 10-11-19, #639-69.

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. The Mammillaria plumosa cluster measured approximately 1 1/2″ tall x 3″ wide. It measured 3/4” tall x 2 1/4” wide when I received it on 9-22-18.

Mammillaria plumosa on 10-11-19, #639-70.

I have several neat cactus in my small collection and the Mammillaria plumosa is definitely one of the most interesting.

Mammillaria plumosa flowers on 11-2-19, #646-5.

I was very happy when I saw a few buds poking upon the Mammillaria plumosa and after a while, the flowers started to open. November 2 was a nice spring-like day so I took several cactus outside to get some good photos of their flowers.  Llifle says they produce yellowish-white flowers sometimes with pink mid-stripes and have a strong scent. Well, I didn’t think to sniff the flowers to check.

Mammillaria plumosa flower on 11-2-19, #646-6.

To me, the flowers are more of a creamy-white, but they do have a very faint pinkish stripe down the middle.

AWESOME!

Mammillaria plumosa repotting on 11-13-19, #649-14.

Several cactus and succulents needed to be re-potted so I started doing that on November 13. Some just needed their soil changed while others needed bigger pots. I used about 50/50 Miracle Grow Potting Soil and pumice for the mix. There are many recipes online for cactus and succulents, but I prefer something simple. I had used a mixture of 2 parts potting soil with 1 part chicken grit and 1 part perlite for many years then read where succulent enthusiasts prefer pumice. SO, I have been trying that since the fall of 2018 with favorable results. I repot any time of the year as necessary, but I have found Fall is a great time. After a summer of regular watering, the potting mixture can become kind of hard when it is decreased. Repotting in the Fall gives the plants nice and loose soil for the winter.

Usually, you shouldn’t increase the pot size that much for cactus because they don’t have a very extensive root system. Too much soil under their roots where moisture isn’t used can cause their roots to rot. I use an old aluminum nail (that mom bought MANY years ago for baked potatoes) to tamp the potting soil between the plant and the side of the pot.

Mammillaria plumosa repotting on 11-13-19, #649-15.

Always make sure to center the plant in the pot and make sure they are standing straight. You wouldn’t want your plants to feel lop-sided. 🙂

Mammillaria plumosa in its new pot on 11-13-19, #649-16.

Sometimes the flowers are open and sometimes they are closed. Old flowers fade and fall off and a few new buds emerge and eventually open.

Mammillaria plumosa on 11-18-19, #653-4.

Many cactus grow very slowly and waiting for their buds to open can get ridiculous. Once you notice a few buds, you look every day to see how big they are. Eventually, you forget about them, and the next thing you know you have flowers. Wait too long and it’s too late. Patience, so it is said, is a virtue.

<<<<2020>>>>

Mammillaria plumosa (Feather Cactus) at 1 3/8″ tall x 3 1/4″ wide on 10-15-20, #747-75.

I had to bring the potted plants inside for the winter on October 15 (2020) because an “F” was in the forecast. As always, I took photographs and measurements. The Mammillaria plumosa did very well over the summer and the tallest in the group was 1 3/8″ tall and the clump was 3 1/4″ wide.

Mammillaria plumosa (Feather Cactus) on 11-6-20, #755-3.

I took a few more photos of this cactus as I am writing the post Fall 2020 Update Part 5: The Mammillaria Group. I had to get a few close-ups of the Mammillaria plumosa flowers.

Mammillaria plumosa (Feather Cactus) on 11-6-20, #755-4.

I think this hole is where an old flower was. 🙂

USEFUL INFORMATION:
Family: Cactaceae
Origin: Coahuila, Nuevo León, & Tamaulipas in Mexico.
Zones: USDA Zones 9a-11 (20-40° F)
Size: Around 5” tall x 16” wide clumps
*Light: Sun to light shade
**Soil: Very well-draining soil. Potting soil amended with pumice (50/50) or additional perlite and chicken grit (2-1-1).
***Water: Regular watering during the summer and barely in the winter. Keep water off the spines (feathers) for best appearance… Well, mine is outside during the summer rain or shine… 🙂

*During the summer, I keep most of my cactus on the back deck where they receive full sun. During the winter most cactus aren’t picky about the light because they are basically dormant. For several winters, mine were in front of the east-facing sliding door in the dining room so they didn’t get much light but they did great. I built a new shelf for the bedroom so now they are in front of a west-facing window. Most of the succulents are on a shelf in a south-facing window in a cool bedroom but a few are in my bedroom.

**When it comes to potting soil, finding the “sweet spot” is not exactly that easy when materials are limited. Cactus and succulent enthusiasts (and experts) do not recommend using peat-based commercial mixes but what choice is there for most of us. They say to use a loam-based mix… Hmmm… Our soil is loam, so do I just use dirt? Well, no because “dirt” is heavy and you need a “light” material. There is A LOT of cactus and succulent recipes online and some get pretty elaborate. Many say to use sand as an ingredient, but if you do that, it needs to be very coarse, like builders sand, because “ordinary” sand, like for sandboxes, is too fine and it clogs up the air space between the coarser ingredients. For MANY years I used 2 parts Miracle Grow or Schultz Potting amended with an additional 1 part of perlite and 1 part chicken grit. Schultz doesn’t seem to have as many large pieces of bark. Cactus and succulent enthusiasts recommended using pumice instead of perlite and grit so I checked it out… The “guy” at General Pumice (online) recommended using a 50/50 mix of potting soil and pumice. General Pumice has 3 different sizes to choose from depending on the size of the pot. SO, in 2018 I bought a bag of 1/8″ and mixed it 50/50 with Miracle Grow Potting Soil. I liked it pretty well. Then in 2020, since most of the cactus were in larger pots, I ordered the 1/4″ size. Pumice has a lot of benefits over perlite and has nutrients that are added to the soil when watering. Pumice is also heavier so it stays mixed in the soil instead of “floating” to the top. Still, there is the issue of the mix getting very hard once you stop watering the plants during the winter when you stop watering. I think this is because of the peat in the potting soil… SO, instead of re-potting the cactus and succulents in the spring, I started doing it during the fall and winter so their soil would be loose. Since you don’t water as frequently during the winter if at all, the timed-release fertilizer does not activate. I have not tried coir, but I am looking into it… 

I think a lot of growing tips online are written by people who never grew succulents and cactus. They just copy from one website and paste it to theirs. You have to sort of mimic the soil where species grow in their native habitat. For that, you almost have to go see for yourself… Typically, they grow in fairly rocky soil

***I water my cactus and succulents on a regular basis during the summer but barely ever in the winter (maybe a little in January) until close to time to take them back outside. 

You can read my Cactus Talk & Update and Cactus & Succulent Tips to get my opinion about growing cactus and succulents.

When you bring your new plants home from the store, you need to check their roots and the soil to see if they are wet. If so, you may want to re-pot it right away. It is advisable to re-pot them in a better potting soil more suitable for cactus and succulents.

I will continue adding more photos and information as time goes by. This plant will definitely be 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. You can also send an email to thebelmontrooster@yahoo.com.

FOR FURTHER READING:
PLANTS OF THE WORLD ONLINE (GENUS/SPECIES)
WIKIPEDIA (GENUS/SPECIES)
LLIFLE (ENCYCLOPEDIA OF LIVING FORMS)
DAVE’S GARDEN
CACTUSGUIDE
THE NATIONAL GARDENING ASSOCIATION
ROYAL HORTICULTURAL SOCIETY
MAMMILLARIAS.NET
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