The more or less upright, sometimes arched or prostrate, blue-green or gray-green, glaucous shoots are almost round and have a diameter of 2 to 4 centimeters.

The needle-like, initially reddish to almost white thorns later turn gray with a black tip.

[3] Harrisia pomanensis is widespread in southern Paraguay, Bolivia and northern Argentina at elevations of 200 to 1200 meters.

[6] The specific epithet pomanensis refers to the occurrence of the species near Pomán in the Argentine province of Catamarca.

Nathaniel Lord Britton and Joseph Nelson Rose placed the species in the genus Harrisia in 1920.