Scientific Name
Ferocactus glaucescens f. nudus
Accepted Scientific Name
Ferocactus glaucescens (DC.) Britton & Rose
Synonym(s)
Ferocactus glaucescens f. inermis
Scientific Classification
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Cacteae
Genus: Ferocactus
Etymology
The cultivar epithet "nudus" (pronounced "NEW-dus") means "unclothed, nude, naked" and refers to the spinless stems of this form.
Origin
Ferocactus glaucescens f. nudus is a form of Ferocactus glaucescens with spineless stems.
Description
Ferocactus glaucescens f. nudus, also known as Ferocactus glaucescens f. inermis, is a slow-growing cactus with spherical to somewhat elongated stems depressed at the apex. The stems can grow solitary or basally suckering, reaching a height of up to 22 inches (55 cm) and a diameter of up to 20 inches (50 cm). They have few or no spines and 11 to 15 acute, somewhat tuberculate ribs up to 0.8 inches (2 cm) in depth. The areoles are greyish-white, felted, circular to oblong, and up to 1.2 inches (3 cm) apart.
The flowers are funnel-shaped, lemon yellow, and appear near the crown in late spring and summer. They can reach a diameter of up to 1.6 inches (4 cm). The fruits are white and spherical, with remnants of the flowers attached. They can grow up to 0.8 inches (2 cm) in diameter.

How to Grow and Care for Ferocactus glaucescens f. nudus
Light: Select a location that receives direct sunlight during most or all of the day. This cactus might etiolate or lean towards light sources if it does not get enough sunlight. A sunny window is a good spot to grow F. glaucescens f. nudus indoors. Rotate the pot a quarter turn every two weeks to encourage balanced growth.
Soil: F. glaucescens f. nudus requires a porous soil with excellent aeration and drainage. Use commercial soil mixes designed for cacti or create your own with a mixture of 70% to 80% mineral grit, such as coarse sand, perlite, or pumice.
Hardiness: This cactus tolerates extreme heat but cannot tolerate freezing temperatures for extended periods. F. glaucescens f. nudus can withstand temperatures as low as 30 to 50 °F (-1.1 to 10 °C), USDA hardiness zones 10a to 11b.
Watering: During the growing season, from spring to fall, water deeply and allow the soil to dry out completely before watering again. Keep the soil dry in winter.
Fertilizing: Feeding your F. glaucescens f. nudus will help to encourage healthy growth. Use a balanced, water-soluble fertilizer, diluted to 1/4 strength, from spring to fall. Do not fertilize during the winter.
Repotting: This cactus does not require frequent repotting. Repot only when it is outgrowing its pot. Pick a container with drainage holes.
Propagation: If you have a specimen with offsets, F. glaucescens f. nudus is easy to propagate by dividing them during the growing season.
Learn more at How to Grow and Care for Ferocactus.
Toxicity of Ferocactus glaucescens f. nudus
F. glaucescens f. nudus is generally non-toxic to humans and pets.
Links
- Back to genus Ferocactus
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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