Mammillaria spinosissima is a fast-growing cactus originating from Mexico. Commonly known as Spiny Pincushion Cactus or Red Headed Irishman, this cylindrical plant is quite easy to cultivate. The winter-dormant plant belongs to the Cactaceae family and grows up to 12 inches in height. The purple-colored flowers of these cacti look truly exceptional. 

Growth rate

The Spiny pincushion cactus has a fast growth rate. The plant is not very demanding.

Flowering

You get to enjoy seeing purple-yellow blooms from early to mid-summer. The cactus is certainly a must-have in your cactus collection.

Watering

Summertime irrigation should be consistent but not excessive. In winter, maintain dryness with plenty of airflow. Low air humidity during the dormancy period is recommended. 

Soil

This species prefers regular cactus mix soil that is quite porous and contains minimal organic materials.

Hardiness
The Red Headed Irishman cactus is hardy in zones 8 to 11. It is frost-resistant and cannot survive in temperatures less than 23° F (-5° C).

Light

This Mammillaria species prefers bright, direct sunshine but needs partial shade as well. If left in the sun's direct rays for too long, susceptible to sunburn.

Propagation

The propagation of these cacti can be done by seeds or cuttings.

The Mammillaria spinosissima red headed Irishman grows best indoors, though pots can be transferred to a sunny, protected patio in the middle of the summer. Check this one on Planet Desert!

Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz

Bloom Season	Earlymid summer
Botanical Name	Mammillaria spinosissima
Dormancy	Winter
Family	Cactaceae
Flower Color	Purple yellow
Growth Habit	Cylindrical
Mature Size	12 in
Native Area	Mexico
Resistance	13 °c