Found in Texas and the states of Hidalgo and Querétaro, Mexico, Mammillaria longimamma is a solitary or clumping spherical cactus with heads 5 inches across. It's name comes from the exceptionally long tubercules. It has a large taproot and needs to be in a deeper pot than other cacti but should be watered carefully as a deep pot takes longer to dry out. It produces flushes of large yellow flowers in summer.
     I got this one from Yasir in Pakistan. It was an offset so It should produce more. I also read you can grow them from a single tubercule, I'll have to try that. Trent, a fellow Daves Garden member from Henderson, Nevada, has a mature specimen that flowers profusely. He has graciously given me permission to use the excellent pictures below. Thank you Trent! Click HERE for a gallery of Trents other pics and be sure to check out the gallery of his in the Echinopsis section.