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Bunny Cactus

Cephalocereus senilis, Cactaceae

Sources last read 14 September 2026.

Not yet rated How forgiving it is has not been judged here yet.

Also called monkey cactus, old man cactus, Old Man of Mexico, old man's head and White Persian Cat Cactus.

Bunny Cactus (Cephalocereus senilis), the whole plant.
Mike Peel ( www, CC BY-SA 4.0 · Wikimedia Commons

Toxicity is partly unassessed

  • Listed as non-toxic to cats by ASPCA.
  • Listed as non-toxic to dogs by ASPCA.
  • Not assessed for people. RHS publishes no harm statement for this plant. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.

What the sources say about its care

Light
Full sun
RHS · read 13 September 2026
Water
Well-drained
RHS · read 13 September 2026
Humidity

No source read publishes a humidity figure for any plant on this site. What follows is general guidance for foliage plants.

Most foliage plants prefer more humidity than a heated room gives; succulents are named as an exception
Penn State Extension · read 13 September 2026
Temperature

How cold this tolerates, not what it prefers. No source read for this site publishes a preferred range for a plant indoors.

H1C — 5–10°C 5–10 °C
RHS · read 13 September 2026
Soil
Sand; pH Alkaline or Neutral
RHS · read 13 September 2026
Toxic to cats
Non-toxic
ASPCA · read 13 September 2026
Toxic to dogs
Non-toxic
ASPCA · read 13 September 2026
Harmful to people
No statement of harm to people is published for this plant; that absence is not evidence it is safe.
RHS · read 13 September 2026

Routine care

Watering
Water the plants thoroughly and let them dry out before the next watering. Kept well fed and watered through the warmest months and adjusted to full sun, it can grow 7 inches each year.
NC State Extension · read 13 September 2026
During growth water generously; at other times keep nearly dry.
RHS · read 13 September 2026
Feeding
Feed monthly with a balanced fertilizer while the plant is growing. Hold back water and fertilizer in winter.
NC State Extension · read 13 September 2026
Propagation
Being widely propagated and popular in cultivation may lessen pressure on wild populations.
NC State Extension · read 13 September 2026
Sow seed in early spring. Alternatively, take cuttings from young branches in early summer or late spring and root them.
RHS · read 13 September 2026
Pruning
Pruning is not needed.
RHS · read 13 September 2026
Pests and diseases
Can be troubled by mealybugs and scale insects.
NC State Extension · read 13 September 2026
Can be troubled by scale insects and mealybugs. Diseases: usually none, but overwatering causes rot.
RHS · read 13 September 2026

Move something and watch

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About the plant

Cephalocereus senilis, the old man cactus, is a species of cactus native to Hidalgo and Veracruz in central Mexico. It is threatened in the wild, but widespread propagation and popularity in cultivation have reduced the demand on wild populations.

From Wikipedia, CC BY-SA 4.0 · read 13 September 2026

Native range
NE. Mexico (to Veracruz)
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
North Eastern Mexico to Veracruz
NC State Extension · read 13 September 2026
Climate
desert or dry shrubland
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Growth form
succulent shrub or tree
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Perennial, Succulent; habit columnar, erect
NC State Extension · read 13 September 2026
Columnar upright (evergreen)
RHS · read 13 September 2026
Size
Height 36–480 in; width 6–12 in
NC State Extension · read 13 September 2026
Height Higher than 12 metres; spread 0.1-0.5 metres after 20–50 years
RHS · read 13 September 2026
Flowering
Flowers gold/yellow, red/burgundy, white; blooms in spring, summer
NC State Extension · read 13 September 2026
Flowers red in summer; yellow in summer; pink in summer
RHS · read 13 September 2026
Uses

What sources record people using this plant for. A traditional or medicinal use listed here is a record of use, not advice to eat it or treat anything with it.

Usually grown as a houseplant or in containers.
NC State Extension · read 13 September 2026

More of the Cactaceae family

Plants with similar care

Sources

What this does not cover

The figures above are what published sources say, not measurements of the plant in your room. They say nothing about your pot size, your water, the season, or how far from the glass the plant stands, and those decide more than any figure here does.

Humidity has no species figure because no source read for this site publishes one, and the only temperature published for this plant is a cold floor. The simulator fills those gaps with general figures for its kind of plant, marked as general and listed on how we read sources. Where a toxicity row says the plant was not assessed, that is the absence of a finding and not a finding of safety.

If something is already wrong, the diagnosis tool asks about the soil, the window and the watering, which is where the answer usually is.