Harrisia aboriginum is a cylindrical-stemmed cactus with “columnar stems upright or reclining with 9-11 ridges up to 6m (20 ft) base to tip." This cactus occurs in Florida in coastal strand vegetation (relatively low salt-tolerant shrubs and grasses), tropical coastal hammocks with trees including gumbo limbo (Bursera simaruba), wild lime (Zanthoxylum fagara), or live oak (Quercus virginiana). Populations are likely to be on shell mounds created by pre-European local residents, or at least on sites with shelly substrates. Plants may be quite close to the mangrove zone, but not in it.