Old Lady Cactus

Mammillaria hahniana

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
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Cactus and Succulents

Water Requirements:

Drought-tolerant; suitable for xeriscaping

Sun Exposure:

Sun to Partial Shade

Light Shade


Unknown - Tell us

Foliage Color:

Unknown - Tell us


under 6 in. (15 cm)


3-6 in. (7-15 cm)


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

Bloom Color:


Bloom Characteristics:

Unknown - Tell us

Bloom Size:

Unknown - Tell us

Bloom Time:

Late Spring/Early Summer

Other details:

Unknown - Tell us

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:


Propagation Methods:

From woody stem cuttings

Allow cut surface to callous over before planting

From seed; direct sow after last frost

By grafting

Seed Collecting:

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:

Queen Creek, Arizona

Siloam Springs, Arkansas

Castro Valley, California

Templeton, California

Vista, California(9 reports)

Cantonment, Florida

Lake Mary, Florida(2 reports)

Henderson, Nevada

Austin, Texas

Brady, Texas

South Jordan, Utah

show all

Gardeners' Notes:


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

bob... read more


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.