Cactus
Golden Barrel Cactus
Echinocactus grusonii · Cactaceae
Also called: Golden Ball Cactus, Mother-in-Law's Cushion, Mother-in-Law's Seat
Golden Barrel Cactus (Echinocactus grusonii) is a low-water cactus well suited to Tucson and the low desert. It's a slow-growing cactus. Expect yellow blooms late spring to summer.
Golden Barrel Cactus at a glance
- Water use
- Low (established)
- Sun
- Full sun to light afternoon shade (young plants and west exposures may scorch; some afternoon shade prevents sunburn in Tucson)
- Mature size
- 24-36 in H x 24-36 in W (slowly to 3 ft+; clusters with age)
- Growth rate
- Slow
- Bloom
- Yellow, Late spring to summer; flowers form a ring at the woolly crown, mostly on mature plants (15+ years)
- Cold hardiness
- Hardy to about 20-25 F; damaged below ~20 F. USDA zones 9a-11; protect from hard frost.
- Soil
- Fast-draining, gritty/sandy soil; excellent drainage is essential. Will rot in heavy or poorly drained soil.
- Native range
- NOT native to the Sonoran Desert; endemic to a small area of central Mexico (Queretaro and Hidalgo states), where it is critically endangered in the wild. Widely planted in Tucson as a non-native ornamental.
- Best used as
- Accent/specimen, Container plantings, Rock and cactus gardens, Mass groupings for dramatic effect
- Wildlife
- Limited wildlife value in Tucson; yellow flowers offer some pollen/nectar to bees.
- Toxicity
- Non-toxic; hazard is purely mechanical from the stiff golden spines.
How to grow Golden Barrel Cactus in Tucson & the low desert
Watering
Drought tolerant once established; deep-soak about every 2-3 weeks in summer for best appearance, monthly or less in spring/fall, and keep nearly dry in winter. Overwatering, especially in cold soil, causes basal rot.
Fertilizer & nutrients
Light feeding optional; a dilute low-nitrogen cactus fertilizer once in spring and once in summer can speed growth, but it is not required in good soil. Avoid high nitrogen.
Pruning & care
None; remove only dead or rotted tissue. Do not cut the body.
Notes
Iconic globular cactus with golden-yellow spines and prominent ribs. In Tucson, give it some afternoon shade and reflected-heat protection to prevent west-side scorch, and ensure perfect drainage. Tip plants slightly south as they age to protect the crown from sunburn. Despite ubiquity in desert landscaping, it is a Mexican (not Sonoran) species.
Sources: AMWUA 'Landscape Plants for the Arizona Desert'; University of Arizona Cooperative Extension; Arizona-Sonora Desert Museum; Tucson Botanical Gardens; IUCN Red List (wild status)