Ferocactus gracilis

Ferocactus gracilis

Family: Cactaceae
Common Name: fire barrel cactus
Origin: Ferocactus gracilis originates from Baja California, Mexico. It is found in rocky hillsides, silt flats, gravelly plains, and outwash fans within the southern end of the Sierra de San Pedro Mártir Mountain Range, 10-300 meters above sea level.
Description: F. gracilis is a large ribbed cactus with a solitary green stem that is globular when young, becoming cylindrical with age. The species is covered in numerous spines – 7 to 13 twisted, red, and gray banded central spines; and 8-12 off-white, slender radial spines. From late spring to early summer, mature cacti may bloom, developing large red flowers with yellow stigma and margins.

Interesting Features:
- Ferocactus gracilis has received the Royal Horticultural Society’s Award of Garden Merit for outstanding value in cultivation.
- Additionally, the fire barrel cactus develops a symbiotic relationship with ants, who visit the nectaries on the plant apex, and in turn protect the fruits from other herbivores.
Uses: When flowering, F. gracilis will attract many bees, and can be a great addition to a pollinator garden. Additionally, the Ferocactus genus has been used extensively for ethnobotanical purposes. The Hualapai people consume the cactus fruits, while the Pima prepare the flesh in a special dish with mesquite pods. In Mexico, Ferocactus species have been used to treat head-ache and other ailments, and are a source of water for Indigenous populations.

Cultivation and Care:

Watering: Moderate
- Water moderately during the summer, thoroughly soaking whenever soil is dry. However, avoid wetting the cactus flesh, to prevent burning and pathogen infection, and never allow to stand in water. As with most cacti, a winter dormancy period should be followed for the best growth – begin to cease irrigation in September, water sparingly in October, and gradually resume watering in March.
Soil: Provide F. gracilis with a well-draining mixture of 10% cactus soil, 45% lava grit, sand, or pumice, and 45% compost. However, the species will tolerate poorer soil if well-draining, and if pH is maintained between 6.6 to 7.5.
Lighting: Full sun is required in order to fully develop the spines, but some shade should be supplied during hot summer afternoons. However, if necessary, moderate shade can also be tolerated. Before introducing to direct sun, plants should be hardened off, to avoid scorching.
Propagation: The fire barrel cactus propagates exclusively through seed, which should be collected from over-ripe fruits and dried. To encourage survival, germinate in vitro in gelatin, agar, or other growth mediums.
Cold Tolerance: 20°F, USDA hardiness zones 9a to 11.
Special Accommodations: In spring, younger plants should be repotted every other year, and mature plants every 4 years to provide fresh soil. Fill the bottom of the container with rocks or gravel to aid drainage, and do not water for the week following repotting. Cacti not planted in compost should be fed with a high potassium fertilizer during the summer – but do not fertilize from September to spring, to avoid lush winter growth. If flowering is desired, the winter dormancy period should be followed strictly, with reduced water and lowered temperatures.

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