The dark green shoots have a diameter of 2 to 6 centimetres (0.8 to 2.4 inches) and are 2 to 3 metres (7 to 10 feet) long.

The five to eight needle-like, ascending, initially black thorns later turn gray and are 4 to 5 centimetres (1.6 to 2.0 inches) long.

[1] Harrisia earlei is widespread in Cuba in the Pinar del Río province on steep limestone cliffs in deciduous bushes at elevations of 100–400 meters.

[2] The first description was made in 1920 by Nathaniel Lord Britton and Joseph Nelson Rose.

[3] The specific epithet earlei honors the American botanist Franklin Sumner Earle (1856–1929).