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cactusArizona NativePet FriendlyPollinator Plant

Saguaro

Carnegiea gigantea

Saguaro

The towering icon of the Sonoran Desert, providing critical habitat for birds and nocturnal pollinators alike.

Hardy to about 20°F in USDA zones 9-11; a true low-desert plant that shrugs off extreme heat, though hard frost can scar the tip and arms.

AMWUA Notes

Extremely drought-adapted; stores water in its pleated trunk and needs no irrigation once established.

Care Guide

💧Watering

Established saguaros need no supplemental irrigation; water a newly transplanted specimen deeply once a month through its first two summers, then stop. Overwatering causes root and basal rot.

✂️Pruning

No pruning needed; only remove arms or tissue damaged by frost or bacterial necrosis, sterilizing tools between cuts.

🌱Fertilizing

None required; saguaros thrive in lean desert soils and gain nothing from fertilizer.

🛡️Pests

Watch for bacterial necrosis (black oozing lesions) and, on stressed plants, longhorn cactus beetles; keeping the base dry is the best defense.

☀️Seasonal Notes

Provide afternoon shade cloth the first summer after transplanting to prevent sunburn, and protect the growing tip from hard frost.

Soil, Feeding & Propagation

🪨Soil

Fast-draining rocky or decomposed-granite desert soil; very low organic matter

💧Drainage

Needs sharp, fast-draining soil.

🌱Nutrient Needs

None — thrives in lean desert soil without fertilizer.

🌰Propagation

Seed (extremely slow, over decades)

📐Spacing

8-10 ft from walls and other plants

🌳Roots & Placement

Shallow, wide, non-invasive root network that is no threat to hardscape; site the massive spiny trunk well away from walkways

Placement Tips

  • •Plant well away from walkways, pools and play areas since the spines and mass are hazardous.
  • •Keep the shaded (north) side facing the same direction it grew in the nursery to prevent sunscald.
  • •Allow at least 8-10 ft clearance from walls and structures for the 40 ft mature height.
  • •Set on a slight mound in fast-draining native or decomposed-granite soil.

Features

Iconic columnar formNocturnal white bloomsWildlife habitatArizona state symbol

Best Uses

SpecimenNatural landscapeHeritage planting

Ecological Value

Attracts

nocturnal pollinatorsbirds

Wildlife Value

nesting birdsbats

Quick Stats

Water NeedsVery Low (Xeric)
Sun Exposurefull sun
Mature Size40 ft H × 10 ft W
Growth Rateslow
Maintenancelow
HardinessUSDA 9-11
FoliageEvergreen
Drainagesharp, fast-draining
Bloom SeasonLate spring
Bloom ColorWhite
Litter Levellow
Thornslarge
Native RegionSonoran Desert

Design Styles

desert modernnative habitat

Include in Your Project

Love Saguaro? Our landscape team sources from wholesale nurseries and can incorporate it into your design.

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Use this care guide to maintain your Saguaro. Questions about your landscape? Reach out anytime.

Data from 2024 AMWUA “Landscape Plants for the Arizona Desert” guide.

Saguaro — common questions

Answers for low-desert Phoenix conditions, drawn from this plant’s growing data.

How much water does Saguaro need in Phoenix?

Saguaro is a very low-water cactus once established. Established saguaros need no supplemental irrigation; water a newly transplanted specimen deeply once a month through its first two summers, then stop. Overwatering causes root and basal rot. Extremely drought-adapted; stores water in its pleated trunk and needs no irrigation once established.

How big does Saguaro get?

Expect roughly 40 ft tall and 10 ft wide at maturity, with a slow growth rate. Allow about 8-10 ft from walls and other plants of spacing when planting. Shallow, wide, non-invasive root network that is no threat to hardscape; site the massive spiny trunk well away from walkways.

Can you plant Saguaro near a pool?

Not ideally. Saguaro is not rated pool-friendly, so it is better placed away from the pool deck and skimmer. Litter is rated low.

Can Saguaro handle Arizona heat and winter frost?

Saguaro is hardy in USDA 9-11 and wants full sun. Hardy to about 20°F in USDA zones 9-11; a true low-desert plant that shrugs off extreme heat, though hard frost can scar the tip and arms. Provide afternoon shade cloth the first summer after transplanting to prevent sunburn, and protect the growing tip from hard frost.

Does Saguaro have thorns?

Yes — Saguaro has large thorns. Site it back from walkways, seating and pool decks where people brush past.

Is Saguaro safe around pets?

Saguaro is listed as pet-friendly in this guide. If your dog is a determined chewer, check any new plant with your vet before planting.

When does Saguaro bloom in Arizona?

Saguaro blooms in late spring, with white flowers. The bloom draws nocturnal pollinators, birds.

How much maintenance does Saguaro need?

Saguaro is low-maintenance. Leaf, flower and pod litter is rated low. No pruning needed; only remove arms or tissue damaged by frost or bacterial necrosis, sterilizing tools between cuts.

What kind of soil does Saguaro need?

Fast-draining rocky or decomposed-granite desert soil; very low organic matter. It needs no supplemental feeding. None required; saguaros thrive in lean desert soils and gain nothing from fertilizer.

Is Saguaro native to Arizona?

Yes. Saguaro is native to Arizona and to the Sonoran Desert, so it is adapted to local rainfall, soil and heat.