By: Bonnie L. Grant, Certified Urban Agriculturist
The mammillaria old lady cactus has no features similar to an elderly woman, but sometimes there is no accounting for names. This is a diminutive cactus with white spines running up and down, so perhaps that is where the resemblance occurs. This native of Mexico likes well-draining soil and warm temperatures and can be grown outdoors in hot climates or indoors as a houseplant.
What is an Old Lady Cactus?
Mammillaria is a large genus of cacti that are mostly native to Central America. Old lady cactus care is super easy, which makes it a perfect plant for a beginner succulent owner. With good care and the right situation, the plant may even surprise you with its classic hot pink, old lady cactus flower.
Mammillaria hahniana is a rounded, chubby little cactus with up to 30 short white spines per areole. The entire effect is of a small barrel cactus covered in snowy fur. These cacti grow 4 inches (10 cm.) tall and 8 inches (20 cm.) wide.
Over time mature cacti form little offsets, which can be divided away from the parent plant and used to start new plants. In late winter to early spring it will develop funnel shaped, hot pink flowers with bright yellow anthers that last quite a while. The flowers may form a ring around the top of the plant. Rarely, small orange fruits will follow.
Growing Mammillaria Old Lady Cactus
You can plant outdoors in USDA zones 11-13 or use them in a container and move inside for fall and winter. Either way, the cactus requires well-draining soil that is on the gritty side.
Place the plant in full sun to partial shade and plant outdoors where there is some protection from western sun, which can cause sun scald. These cacti need four to six hours of bright light to thrive.
In order to promote the old lady cactus flower, provide a slightly cool area in winter. During this time, suspend watering and let soil dry completely.
Old Lady Cactus Care
The downy little cacti really thrive on neglect. Provide water in the driest periods and gradually reduce in fall.
You don’t necessarily have to feed these plants but in pot bound specimens, a spring feed of diluted cactus food is appreciated. Repot container plants every couple of years with a good cactus mix or make your own with one part topsoil, one part fine gravel or sand, and one part perlite or pumice.
When repotting, allow the soil to dry out to easily remove the plant and don’t water the new soil for several days to allow the plant to acclimate.
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Read more about Cacti & Succulents
How to Grow and Care for Mammillaria
Mammillaria is one of the largest genera of family Cactaceae with about 200 to 300 species, depending on several classifications. Most species are native to Mexico, but some come from the southwestern United States, Guatemala, Honduras, the Caribbean, Colombia, and Venezuela. The genus includes plants known commonly as Pincushion Cactus, Nipple Cactus, Fishhook Cactus, or Bird's Nest Cactus.
The generic name "Mammillaria" derives from the Latin "mammilla," meaning "nipple or teat," and refers to the tubercles that are among the distinctive characteristic of the genus. In the early 1800s, some authors have used the spellings "Mamillaria" and "Mammilaria," however, the accepted spelling for this genus is "Mammillaria."
The first species, Mammillaria mammillaris, was described by Carl Linnaeus as Cactus mammillaris in 1753. Adrian Hardy Haworth first described the genus in 1812.
Mammillarias are small cacti with globose or short cylindrical stems which grow either solitary or in clumps. The stems vary among species from 0.4 to 8 inches (1 to 20 cm) in diameter and 0.4 to 16 inches (1 to 40 cm) in height. Some species form mounds of more than 100 stems that can reach over 3.3 feet (1 m) in diameter. All species have spirally arranged tubercles with areoles and spines at the ends. The tubercles are conical, cylindrical, pyramidal, or round. Spines can be few or many, stiff, bristle-like, or hair-like. In the axils, between the tubercles, there can be wool or bristles or both. Flowers are funnel-shaped and range from 0.3 to 1.6 inches (0.7 cm to 4 cm) in length and about the same in diameter. They come in a wide range of colors, from white, greenish, and yellow to pink and red, often with a darker mid-stripe. Mammillarias typically start flowering in their second year, often forming a ring around the stem. Fruits are club-shaped or elongated, usually red but sometimes white, yellow, green, or magenta. Seeds are brown or black.
Old Lady Cactus
|Family:||Cactaceae (kak-TAY-see-ee) (Info)|
|Genus:||Mammillaria (mam-mil-AR-ee-uh) (Info)|
|Species:||hahniana (hahn-ee-AY-na) (Info)|
|Synonym:||Mammillaria hahniana subsp. hahniana|
|Synonym:||Mammillaria hahniana var. hahniana|
Drought-tolerant suitable for xeriscaping
USDA Zone 9a: to -6.6 °C (20 °F)
USDA Zone 9b: to -3.8 °C (25 °F)
USDA Zone 10a: to -1.1 °C (30 °F)
USDA Zone 10b: to 1.7 °C (35 °F)
USDA Zone 11: above 4.5 °C (40 °F)
Where to Grow:
Can be grown as an annual
Plant has spines or sharp edges use extreme caution when handling
Soil pH requirements:
Allow cut surface to callous over before planting
From seed direct sow after last frost
Allow unblemished fruit to ripen clean and dry seeds
Properly cleaned, seed can be successfully stored
This plant is said to grow outdoors in the following regions:
Vista, California(9 reports)
Lake Mary, Florida(2 reports)
On Oct 12, 2008, aww07 from Siloam Springs, AR wrote:
I bought this plant yesterday at the low's garden center out of the 200 cactus's they had this one stood out the most it was so small and on sale for $1 it looked hariy and not very sharp but when i went to pick it up I recieve numberous needles in my hand. It is a very cute cactus though. I don't know how easy it is to grow i ready it was easy but i've only had it for a day so i dont know.
On Dec 27, 2005, thistlesifter from Vista, CA wrote:
Harry Johnson developed cultivars of m. hahniana and sold them by mail order in the early-to-mid 1900's.
When Harry's nursery was sold after his death in the late 1980s some of the specimens of m. hahniana that he used to develop the cultivars were made available. I submitted a picture of one of the ancestors to the present long-haired cultivars of m. hahniana. This specimen came directly from his nursery to our gardens.
It is grown here in container, which I find is the most successful way to grow clustering mams here. We have lost many mams to rot even in fast draining mounds growing out of pots. They seem to do much better in fast draining pots.
Of course, greenhousing is best, but that was in a different life. lol
On Mar 12, 2005, Xenomorf from Phoenix, AZ (Zone 9b) wrote:
The differences between the subspecies are:
--ssp. hahniana has only 1 central spine and 20-30 radial spines per areole. Flowers are purplish-red.
--ssp. bravoae has 2 central spines and 28-30 radial spines per areole. Flowers are dark pink.
--ssp. mendeliana has 2-4 central spines and under-developed or zero radial spines. Flowers are pale pink.
--ssp. woodsii has 2 central spines and 25-30 radial spines per areole. Flowers are pink.
On Feb 22, 2005, hanna1 from Castro Valley, CA (Zone 9a) wrote:
Beautiful globular cactus is covered with white spines and dense white hair. Rings of vivid carmine flowers in Summer create dramatic contrast with white hairs. It is a native of Mexico. Bright light. Porous cactus soil. Water thoroughly when soil is dry to the touch. Protect from frost.
On Feb 22, 2005, cacti_lover from Henderson, NV (Zone 9b) wrote:
Contrary to the hardiness detail above, this cactus can survive to 25F. It is easy to grow, but rot prone if root is wet in winter. Flowers in late winter to mid spring depending on what zone it is in. The ring of pink flowers is pretty and can last for weeks, but each individual flowers last for only a few days.
On Apr 4, 2001, Ehowell from Weyburn, SK wrote:
This little cactus is very easy to grow. The round body has silky hairs and tiny white "cotton balls' all over it. The little pink flowers keep coming all winter in my south window.
3. Saguaro Cactus (Carnegiea gigantea)
The slow-growing nature of saguaro makes it an excellent plant for your desk. Another great trait that makes saguaro a perfect workmate in your office is that it doesn’t require too much watering. If you’re the kind of person who travels a lot for work and has to leave your plant uncared for long, you’ll love saguaro. Just make sure you give it some sparing watering once a month, and it will appreciate.
But one thing you should never deny saguaro is light. Ensure there’s some bright light coming in through your office windows. The beauty of saguaro lies in its barrel-shaped bodies and pleated trunk interior. The pleats in the plant enable it to gather water and store it in its tissues for the longest time.
As for the blooms, it will take you a very long time before you see any. Experienced gardeners say it can go up to 35 years without blooming. But even without any flowers, saguaro still looks stunning in its majestic and treelike appearance. When it’s ready to produce flowers, you’ll notice them at the end of the arms or the sides of the cactus. The blossoms will open at night and close during the day, so you must be accurate with your timing to notice some.
How to Propagate Hairy Cactus
You can easily propagate types of hairy cactus from seeds. If you already have a hairy cactus species, you can collect fresh and high-quality seeds from your own plant. If not, you can purchase the seeds you want from reputable sources.
Then, all you need to do is sowing the seeds in soil that drains well. You can sow them outdoors in zones 9 and 10 for plants. You can also do it indoors under a grow light or on a heated seed mat.
You can also propagate different types of hairy cactus by cutting a small branch from them and rooting it. However, this method inevitably leaves an unpleasant scar near the main stem’s base. If you want to remove an offset to use in propagation, let it dry for a week so the wound heal. Rooting usually occurs in 3 to 8 weeks. Therefore, it is best to propagate any hairy cactus species from seed.