Among the mamillarias or pin cushion cactus are some particularly exquisite species. These include the following.
Mother of hundreds (Mamillaria compressa)
This plant is particularly attractive. It is named for the many crowded offsets all clustered together that develop from older plants. The individual stems are globular, and greenish-blue. These can be nearly eight inches tall. The pronounced tubercles are covered with slender white spines, and the white, woolly bristles that arise from the axils. The blossoms are pink to reddish-purple.
South American pin cushion (Mamillaria columbiana)
Originally native to Colombia, the Latin name for this species was chosen for its place of origin. This plant tends to be solitary rather than clumping. Greenish-gray in color, it is also more elongated or cylindrical than the other mamillarias. It reaches nearly ten inches in height. There are two types of spines with the larger ones being white while the others are brownish-red. The dark pink blossoms have yellow centers.
Whitey mamillaria (Mamillaria geminispina)
Native to Mexico, this clustering plant is initially club-like. But over time it becomes more cylinder-like. It reaches over seven inches in height. The blue bodies have a whitish tinge. The tubercles look like knobs. It is covered with soft hair-like bristles from the axils of the tubercles. The blossoms are scarlet. This is an excellent choice as a houseplant.
This soft green, cylinder-shaped plant is literally covered with sharp white, needle-like spines. It can rach four inches in height with a diameter of three inches. The blossoms are red. Opening in the spring, these are less than ½ inch in diameter. Older plants can eventually form clumps.
These grow in large clusters, and are pretty much cylindrical. The stems are concealed by the short white spines, which have yellow tips. This species is less than two inches in height.
The blossoms are yellow or white.