Echinocactus platyacanthus aka Biznaga Gigante

Echinocactus platyacanthus is a Mexican cactus in the family Cactaceae. Its native range runs from Nuevo León south to Oaxaca. Kew places it in desert and dry shrubland habitats. It classes the plant as a succulent subshrub or shrub. The RHS also gives Mexico as its plant range. It is not native to Britain or Ireland. The RHS accepts Echinocactus platyacanthus as the correct name.

The ribs change in number as the plant ages. Young plants have between five and 20 ribs. Older plants may have 30 to 60, or even more. These ribs run up and down the stem. They have sharp edges, but their surface changes with age. On young plants, the ribs can show raised bumps called tubercles. Later, the ribs become taller and their edges more even. This change in rib form is one feature of its development. Rib counts therefore span a broad range within the species.

LLIFLE describes two sets of spines: radial and central spines. The radial spines spread out and can form upper and lower groups. Most clusters have four to eight radial spines. Some have as few as three or as many as ten. These spines measure about 0.04–0.13 feet [0.012–0.04 metres] long. The central spines number three or four and also spread outward. They often make a cross, with the lower spine larger. They can curve somewhat rather than remain straight. Their length ranges from about 0.10–0.33 feet [0.03–0.10 metres]. The central spines can thus exceed the radial spines in length.

The fruit turns dry when ripe and has a yellowish colour. Its shape ranges from oblong to a narrow club. Each fruit measures about 0.10–0.26 feet [0.03–0.08 metres] long. Its width is about 0.08 feet [0.025 metres]. Many thin, dry, papery scales cover the fruit. Wool and hairs also occur on its surface. Parts of the flower's perianth remain attached as the fruit develops.

The species-level evidence gives no reliable cultivated height or spread. It also leaves care needs, frost limits, and flowering dates unresolved. The supplied species accounts do not establish edibility or toxicity. Nor do they identify pests, diseases, or specific landscape uses.