Say it: eh-KY-noh-cactus groo-SOH-nee-eye. Common names: golden barrel, golden ball, mother-in-law's cushion.
Where it grows
A small area of central Mexico in the states of Querétaro and Hidalgo. Much of its original habitat was flooded by a dam in the 1990s, and the species is listed as endangered in the wild — yet it's one of the most widely grown cacti on Earth, entirely from seed.
Size and growth
A ribbed globe covered in golden-yellow spines, topped with a woolly crown. Old plants reach 3 feet across and can slowly become barrel-shaped and clump with age. Moderate growth: a seedling can be fist-sized in 3–4 years and dinner-plate sized in about a decade with good care.
Flowers
Small yellow flowers appear in a ring on the woolly crown in summer, but only on mature plants — typically 15 or more years old and over a foot wide. People grow it for the spines, not the flowers.
Care
- Light: full sun for the best spine color; some afternoon shade in the hottest climates.
- Water: regular in summer when dry, little or none in winter.
- Soil: gritty, fast-draining.
- Cold: hardy to around 20°F for short periods if dry. A classic landscape cactus in mild-winter regions.
From seed
Very easy and a great first cactus to sow. Germination in 7–14 days at 75–85°F. Seedlings are green and spineless at first; the gold spines come in during the first year.