Pocket BotanistPlant guide
Saguaro.
Carnegiea gigantea
Pronounced kar-NEG-ee-uh jy-GAN-tee-uh
Also known as Giant Saguaro, giant cactus, sage-of-the-desert, saguaro
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The Saguaro is an iconic symbol of the American Southwest, known for its massive, tree like stature. These slow growing giants can live for over a century in the wild. They are perfectly adapted to survive in harsh, arid desert conditions.
At a glance
- Care level
- Moderate
- Plant type
- Succulent
- Light
- Full sun
- Indoor light
- Direct sun
- Water
- Every 14 to 30 days
- Mature size
- 40 to 60 feet
- Growth rate
- Slow
- Hardiness
- USDA 9 to 11
- Bloom time
- Late spring to early summer
Care
Provide as much direct sunlight as possible to mimic their natural desert habitat. Ensure the soil drains extremely well to prevent root rot, which is the most common cause of failure. Watch for soft spots on the stem, as these indicate the plant is holding too much moisture.
- Watering
- Water deeply during the summer growing season, but let the soil dry out completely between waterings.
- Feeding
- Apply a low nitrogen cactus fertilizer sparingly during the active growing months.
- Pruning
- Pruning is rarely needed, but you can remove dead or damaged tissue with a sterilized blade.
- Repotting
- Repot only when the plant becomes top heavy or clearly outgrows its container.
- Soil
- Sandy, rocky, well draining cactus mix
- Soil pH
- 6.0 to 7.5
- Temperature
- -7 to 45°C
- Humidity
- 10 to 40%
Safety
- People
- The plant is not toxic, but its sharp spines pose a significant physical injury risk.
- Children
- Keep children away from the plant to prevent severe injury from the long, sharp spines.
- Contact allergens
- The sharp spines can cause skin punctures and irritation.
- Airborne allergens
- The pollen may cause mild allergic reactions in sensitive individuals.
- Edibility
- The fruit is edible, but harvesting from wild plants is strictly prohibited and illegal.
How to identify it
- Tall, columnar, ribbed green stem
- Sharp spines along vertical ribs
- Large, white, nocturnal blooming flowers
- Develops characteristic arm branches with age
- Height
- 3 to 12m
- Spread
- 1 to 3m
- Leaves
- green, evergreen
- Flowers
- white, 7 to 12cm
- Fruit
- red, Summer
Problems to watch for
- Bacterial NecrosisCommon
- Root RotCommon
- Mechanical DamageUncommon
Check your saguaro from a photo
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Growing it
- Propagation
- seed
- When to plant
- spring, summer
Plant young saguaros near nurse plants to protect them from extreme sun and frost during their early years.
Grows well with
- Brittlebush · It provides light shade for young saguaros in the wild.
- Palo Verde · This tree acts as a nurse plant for young cacti.
Similar species
- Organ Pipe Cactus · It shares a similar desert habitat but has a different branching habit.
Science
- Family
- Cactaceae
- Genus
- Carnegiea
- Order
- Caryophyllales
- Class
- Magnoliopsida
- Native range
- Sonoran Desert in Arizona and Mexico.
- Conservation
- The saguaro is protected by law in its native habitat, and wild collection is strictly prohibited.
It survives by storing vast amounts of water in its pleated stem to endure long periods of drought.
- Value to wildlife
- nectar source, nesting site
- Pollinators
- bees, butterflies, moths, hummingbirds
- Uses
- ornamental, wildlife habitat
Through the year
Ecological indicators
- Salinity
- 2/9
- Soil reaction
- 7/9
- Light
- 9/9
- Temperature
- 8/9
- Moisture
- 1/9
- Nutrients
- 2/9
Taxonomy resolved against GBIF.
Questions people ask
- Can I grow a saguaro in a pot?
- Yes, they grow slowly in containers but require excellent drainage and intense light.
- How often should I water it?
- Water sparingly during the growing season and keep it completely dry in winter.
Where the name comes from
The genus honors Andrew Carnegie, while the species name refers to its massive size.
Good to know
- Saguaro cacti can live for over 150 years.
- They do not grow their first arm until they are 75 to 100 years old.
- A mature saguaro can weigh several tons after absorbing heavy rainfall.
- The white flower is the state wildflower of Arizona.
Keep your saguaro growing
This page is a general guide. Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked.
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This guide was generated with AI on and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.