Old Man Cactus
Cephalocereus senilis
The Old Man Cactus (Cephalocereus senilis) is named for its shaggy covering of long, white, hair-like spines that resemble an old man's beard. Native to Mexico, this cactus grows slowly into a tall, narrow column and thrives in dry, sunny conditions.
The white “hair” protects it from sun and temperature extremes, while hiding sharper yellow spines underneath. It makes a striking statement in cactus collections and thrives indoors with bright, direct sunlight and minimal watering.
Given the right conditions and enough time (we’re talking decades), it can grow impressively tall — but even small, younger plants have plenty of charm.
Quick Info
- Light: Bright
- Water: Low
- Size: Up to 2 feet indoors
- Humidity: Low
- Temp: 60–85°F (16–29°C)
- Flowering: Yes
- Type: Cactus
- Dog Safe: Yes
- Cat Safe: Yes
- Kid Safe: Yes
Toxicity Info
- Dog Safe: Yes
- Cat Safe: Yes
- Kid Safe: Yes
Care Instructions
- Use a cactus/succulent potting mix with excellent drainage
- Place in full sun or a bright window with lots of direct light
- Water deeply but only every 3–4 weeks (less in winter)
- Avoid getting the fuzzy surface wet to prevent mold
- Rotate occasionally for even growth
Common Problems
- Rot at base: Overwatering or poor airflow
- Discoloration or bald patches: Too little light or water on the fuzz
- Stretching (etiolation): Not enough direct sun
FAQs
Yes — but don’t be fooled. Underneath are stiff yellow spines, so handle with care.
Typically 1–2 feet tall over many years. Outdoors in its native habitat, it can reach 20+ feet.
No — it’s protective and should be left intact.
Related Plants
Barrel Cactus
A round, spiny cactus with golden ribs and a striking sculptural look — the Barrel Cactus is a low-maintenance desert beauty perfect for sunny spots.
Fairy Castle Cactus
A charming, castle-like cactus with columnar stems that resemble towers — the Fairy Castle Cactus is a sculptural, slow-growing favorite for windowsills and small spaces.