Plants grow outside in twenty degrees of frost, but with colder weather than this they must be protected or grown in warm conservatories. They grow easily from seed in the usual way in pots with part shade and with occasional watering to keep the soil moist. They may be transplanted at any season in sandy or gravelly clay, and given enough water to moisten the soil well once in two or three weeks during dry months.
Snowball Pincushion (Mammillaria Oliviæ)
(Named Oliviæ in honor of Mrs. C. R. Orcutt, who shared her husband’s interest in these plants)
How to identify and how it grows
The Snowball Pincushion is covered with a dense coat of white spines, looking much like a snowball lying on the ground. It grows on solitary stems or in some instances in clumps, is globose, and has twenty-five to thirty-five thorns. The plant is covered with radially placed spines about half an inch long, translucent white and somewhat twisted. There are four centrals in the spine groups. The flowers of this plant resemble those of the Sunset Cactus, and are pink and pink-rose with the margins fringed in white. They are very showy and about an inch long. The pink flowers contrast well with the glistening white spines, making this cactus one of the handsomest of its kind, growing on the deserts and foothills of southern Arizona.
How to grow
The same care and treatment is suggested as for the Sunset Cactus.
Green Flowered Pincushion (Mammillaria viridiflora)
(Named from its green flowers, which are very uncommon among cacti)