Mammillaria hahniana (Old Lady Pincushion) is a small cactus, with solitary or clustered stems, that tends to form large clumps over time. At first globular, later cylindrical, the stems, up to 12 in. tall (30 cm) and 4 in. wide (10 cm), are covered with dense white bristles and fine spines. Blooming profusely, it produces a pretty ring of rose-red flowers, 0.5 in long (1 cm). The blossoms are followed by small red fruits that are edible.
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