Plate No. 12
Organ Pipe
Stenocereus thurberi
"A bundle of green pipes"
Native to
Sonoran Desert of Mexico and southern Arizona

History
A brief account
The signature cactus of the Organ Pipe National Monument, this species grows in clusters of vertical ribbed columns. The Tohono O'odham harvest its sweet pitaya fruit, regarded as superior even to that of the saguaro.
How to care for
Organ Pipe (Stenocereus thurberi) grows best when its natural cycle of strong light, freely draining soil and measured watering is respected. Give it full direct sun. Water it according to its seasonal needs: deeply but rarely in summer; nothing through winter. Plant it in mineral-rich, very fast-draining mix. A container with an unobstructed drainage hole is essential, because moisture lingering around cactus roots can quickly lead to rot.
Keep its temperature needs in mind: 5–40°c. brief light frost survivable. During active growth, check the compost before watering rather than following a rigid calendar, since heat, light and pot size all change how quickly it dries. Reduce watering during cool or dormant periods, keep the plant well ventilated, and wait until the growing medium is dry before watering again.
How to propagate
From seed, or by rooting severed column sections. Sow fresh seed on the surface of a fine, sterile cactus mix and keep it warm, lightly humid and out of harsh direct sun until germination. Once seedlings are established, increase ventilation gradually and allow longer intervals between watering to reduce the risk of damping off.
Young cacti are especially vulnerable to excess moisture. Use a small pot with excellent drainage, provide bright filtered light while roots establish, and move the new plant gradually into the light, temperature and watering conditions preferred by a mature Organ Pipe.
Cultivation
Quick tips for care & planting
- Light
- Full direct sun.
- Water
- Deeply but rarely in summer; nothing through winter.
- Soil
- Mineral-rich, very fast-draining mix.
- Temperature
- 5–40°C. Brief light frost survivable.
- Propagation
- From seed, or by rooting severed column sections.