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Plant Profiles / Fairy castle cactus
Photos: Wikimedia Commons
Fairy castle cactus
Acanthocereus tetragonus 'Fairy Castle' · Fairy castle
A clustering cactus with many upright stems of varying heights, like the turrets of a tiny castle. Easy, compact and great for windowsills.
Bright light to full sunLight
Every 2–3 weeksWater
Very easyCare level
Care at a glance
Light
Bright light to full sun
ShadeFull sun
Bright light with some direct sun.
Water
Every 2–3 weeks
DryWet
Water when completely dry.
Humidity
Low
LowHigh
Dry air.
Temperature
10–35°C (50–95°F)
CoolWarm
Keep frost free.
Growth
Slow, clustering
SlowFast
Grows 15–60 cm.
Soil
Cactus mix
LeanRich
Free-draining.
Fertiliser
Twice a year
RarelyOften
Diluted cactus fertiliser.
Pet safety
Non-toxic
SafeToxic
Non-toxic; spines can injure.
About this plant
'Fairy Castle' is a dwarf cultivar of a cactus from Mexico, the Caribbean and Florida. It grows slowly into a dense clump and is one of the easiest cacti to keep indoors.
Best spots
Sunny windowsills, desks in bright light, balcony pots and cactus bowls.
Plant facts
| Botanical name | Acanthocereus tetragonus 'Fairy Castle' |
| Family | Cactaceae |
| Origin | Cultivar (species from Mexico & Caribbean) |
| Plant type | Clustering cactus |
| Mature size | 15–60 cm |
| Growth rate | Slow |
| Spines | Short, pale |
| Flowers | Rare indoors |
| Toxicity | Non-toxic |
| Propagation | Stem cuttings |
Seasonal care calendar
J
F
M
A
M
J
J
A
S
O
N
D
Active growth
Fertilise
Keep dry
Active growthFertiliseKeep dry
Based on Southern Hemisphere seasons.
Troubleshooting
| Soft stems | Overwatering. |
| Leaning stems | Not enough light. |
| Brown patches | Sunburn. |
| Mealybugs | Treat with alcohol. |
| Shrivelled | Underwatered. |
Common questions
Does it flower?
Rarely, especially indoors.
Can I propagate it?
Yes, from dried stem cuttings.
Is it good indoors?
Yes, in bright light.
How big does it get?
Usually under 60 cm.
