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Plant Profiles / Old man cactus
Photos: Wikimedia Commons
Old man cactus
Cephalocereus senilis · Old man cactus
A columnar cactus wrapped in long, shaggy white hairs, like a beard. A quirky statement for sunny spots.
Full sunLight
Every 3 weeksWater
EasyCare level
Care at a glance
Light
Full sun
ShadeFull sun
Full sun.
Water
Every 3 weeks
DryWet
Water only when dry; avoid the hair.
Humidity
Low
LowHigh
Dry air.
Temperature
5–40°C (41–104°F)
CoolWarm
Protect from frost.
Growth
Slow, columnar
SlowFast
Grows 30–60 cm in pots.
Soil
Mineral cactus mix
LeanRich
Gritty mix with lime.
Fertiliser
Twice a year
RarelyOften
Diluted cactus fertiliser.
Pet safety
Non-toxic
SafeToxic
Non-toxic.
About this plant
Native to central Mexico, the old man cactus uses its hairs to shade itself. It grows slowly in pots and needs full sun to keep its hair white and thick.
Best spots
Sunny windowsills, balcony pots and cactus collections.
Plant facts
| Botanical name | Cephalocereus senilis |
| Family | Cactaceae |
| Origin | Central Mexico |
| Plant type | Columnar cactus |
| Mature size | 30–60 cm in pots |
| Growth rate | Slow |
| Spines | Long white hairs hiding spines |
| Flowers | Only on very old plants |
| Toxicity | Non-toxic |
| Propagation | Seed |
Seasonal care calendar
J
F
M
A
M
J
J
A
S
O
N
D
Active growth
Keep dry
Active growthKeep dry
Based on Southern Hemisphere seasons.
Troubleshooting
| Dirty, matted hair | Water the soil only; gently brush. |
| Soft base | Overwatering. |
| Thin hair | Not enough sun. |
| Mealybugs hiding in hair | Check and treat with alcohol. |
| Leaning | Uneven light. |
Common questions
Can I wash the hair?
Gently, with mild soapy water if dusty, then dry in sun.
Does it flower?
Only after many years.
Is it pet safe?
Yes.
Are there spines?
Yes, under the hair.
