Origin and Habitat: Ferocactus peninsulae is the common barrel cactus through the states of Baja California and North West Mexico. Altitude: From sea level to 450 metres above sea level.
Habitat and Ecology: The species occurs in rocky places, in sandy areas and hillsides together with Mammillaria dioica, Cochemiea setispina, Echinocereus ferreirianus and Lophocereus schottii. The species tends to be more common in the south than the north of the Baja peninsula, however, the population is declining. The main threat is illegal collection and habitat destruction due to urbanization and creation of artificial grasslands.
Description: Ferocactus peninsulae is large ribbed barrel cactus with an erect stem becoming cylindric in age and attaining a height of 2.5 metres (but usually about 70 cm), up to 40 across., which is unusual for the genus.
Spines and flowers very similar to those of Ferocactus wislizeni. Cultivated plants can be reliably distinguished from Ferocactus wislizeni var. herrerae only when seeds or details of wild source are available.
Flowers: Broadly funnelform, 5-6 cm long red to yellow with orange to red midveins. Blooming season: Spring to autumn.
Fruit: Globose, yellowish, 2.5-3.5 cm long, bearing broad rounded scales.
Soil: It grows well in a rich, well drained soil such us clay, pumice, lava grit, and only a little peat or leaf-mould, but it isn't picky about soil.
Hardiness: When dormant, the plant is slightly cold tolerant (down to nearly -2° C or less), but when left out it is more sensitive to frost. This plants need a period of cool rest in winter to produce flowers abundantly.