Although restricted in range, this species grows in protected habitat and lacks major threats.

[3][4][5] The flowers appear from March to May, and are a fiery red to orange in color, measuring 3–4 cm (1.2–1.6 in) in length and diameter.

The barrel-shaped fruits reach similar sizes and are lemon yellow with crescent-shaped scales.

[3][4][5] Echinocactus diguetii was described in 1898 by Frédéric Albert Constantin Weber, who named it in honor of its discoverer, Léon Diguet, a French explorer who was investigating pearl fisheries on Isla Santa Catalina.

[4] Britton and Rose noted that the species did not seem to have a definite habitat, growing on from mountainsides along large igneous rocks to old shell beaches.