A number of mamillaria species are recommended as houseplants and outdoor gardens. These include the following.
Birds nest cactus (Mamillaria captotricha)
Native to Mexico, this is noted for the rounded bodies that are up to two inches in diameter. These eventually form a large clump. The vivid green plants have long tubercles. The long slender curving spines are yellow to yellowish-white. These will sometimes be hooked or curving.
The white blooms are green on the outer surface with green tinges towards the throat. These open in the axils, but are frequently concealed from view by the spines. However, they still give off a wonderful fragrance.
Golden stars (Mamillaria elongata)
Native to Mexico, this clumping species is particularly attractive. The individual plants are soft green with tubercles that form neat spirals.
The Latin name for this species refers to the elongated or cylinder-like bodies, which is a little over an inch in diameter. The spines are golden.
The yellow or white blossoms are white. This species needs to be kept pretty dry during the winter months.
Grape cactus (Mamillaria multiceps)
Native to the American Southwest and Mexico, and possibly the Caribbean, this clumping plant eventually develops a large number of small globe-like offsets. The individual segments are less than an inch across. These are deep green and are covered with reddish radial spines as well as other slender spines that may be white or yellow
The blossoms are apricot.
Little suns (Mamillaria microhelia)
Native to Mexico, this grows to about six inches tall. This species produces offsets. It is cylindrical to columnar body has attractive tubercles. The stiff spines are crowded together, and come in various colors, including yellow, white, and reddish-black. Sometimes, they will have white tips. As the plant ages, it tends to develop additional hooked central spines that are reddish-brown. These husky plants reach six inches in height and up to two inches across.
This blooms heavily during the spring and summer. The small, delicate looking blossoms range in color from white to greenish to soft yellow. There can also be hints of pink within the center. The flowers grow to ½ inch in length.