Pediocactus knowltonii (Knowlton's Cactus)

Scientific Name

Pediocactus knowltonii L.D. Benson

Common Names

Knowlton's Cactus, Knowlton's Miniature Cactus, Knowlton's Pincushion Cactus, Knowlton's Minute Cactus

Synonyms

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 genus Pediocactus. This tiny cactus may reach up to 2.2 inches (5.5 cm) tall and up to 1.2 inches (3 cm) in diameter. An individual is considered to be an adult when it exceeds 0.4 inch (1 cm) in diameter. It is spherical or somewhat cylindrical in shape. The areoles are round and covered in hairs. Each areole has up to 26 radial spines which are red, pink, or white in color. The flower is up to 1.4 inches (3.5 cm) long and up to 1 inch (2.5 cm) in diameter, with pinkish tepals, the outer ones sporting brownish midstripes. The fruit is green, ripening reddish and up to 0.2 inch (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 own roots and are cultivated only by skilled and experienced cactus growers. The growing medium needs to be porous so it can drain well and dry out completely. It does best in partial shade and it need protection from the sun during the hottest part of the summer.

They don't like high temperature and humidity levels in greenhouses. This cacti should be placed in a well-ventilated position. They like "wind". Water them moderately from spring to fall and let dry out between waterings. The rest of the year keep them in dormancy.

These cacti are very slow growers. For this reason they are frequently grafted on strong, hardy, cactus stocks like Opuntia and Echinocereus.

The flowers buds stay dormant on the plant apex all winter. They will open in spring when the temperatures rise… – See 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
• Succulentopedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus

Photo Gallery