Scientific Name
Pediocactus knowltonii L.D. Benson
Common Name(s)
Knowlton's Cactus, Knowlton's Miniature Cactus, Knowlton's Pincushion Cactus, Knowlton's Minute Cactus
Synonym(s)
Pediocactus bradyi var. knowltonii, Pediocactus simpsonii var. knowltonii, Toumeya knowltonii
Scientific Classification
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Cacteae
Genus: Pediocactus
Description
Pediocactus knowltonii is one of the smallest cacti in the world and the smallest and rarest species in the genus. The stems are spherical or somewhat cylindrical and grow usually solitary or few together, measuring up to 2.2 inches (5.5 cm) in height and 1.2 inches (3 cm) in diameter. The round areoles are covered in hairs, and each bears up to 26 red, pink, or white radial spines.
The flowers have pinkish tepals, with outer ones sporting brownish mid-stripes, and can reach up to 1.4 inches (3.5 cm) in length and 1 inch (2.5 cm) in diameter. The fruits are green and become reddish as they ripen, and they can grow up to 0.2 inches (0.5 cm) long.
Hardiness
USDA hardiness zones 5a to 11b: from −20 °F (−28.9 °C) to 45 °F (+7.2 °C).
How to Grow and Care
Pediocactus are difficult to grow on their roots and are cultivated only by skilled and experienced cactus growers. The growing medium must be porous to drain well and dry out completely. It does best in partial shade and needs protection from the sun during the hottest part of the summer.
These cacti do not like high temperatures and humidity levels in greenhouses. Pediocactus should be placed in a well-ventilated position. They like "wind." Water them moderately from spring to fall and let the soil dry out between waterings. Then, stop watering and allow them to go dormant for the winter months.
Pediocactus are very slow growers. For this reason, they are frequently grafted on strong, hardy cactus stocks like Opuntia and Echinocereus.
The flower buds stay dormant on the plant apex all winter. However, they will open in spring when the temperatures rise.
Learn more at How to Grow and Care for Pediocactus.
Origin
Pediocactus knowltonii is endemic to San Juan County, New Mexico, in the United States.
Links
- Back to genus Pediocactus
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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