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Ironwood

Olneya tesota

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5 gallon

Ironwood

Out of stock

30'x30'

Sizes:

Desert Ironwood – Olneya tesota
Also known as: Ironwood, Palo Fierro

A keystone species of the Sonoran and Colorado Deserts, Desert Ironwood is a long-lived, evergreen tree in the legume family (Fabaceae), often considered one of the most ecologically important native trees in the Southwest. Typically growing 15 to 30 feet tall with a broad, rounded crown, it can reach up to 45 feet in optimal conditions. Its short, often twisted trunk supports drooping, gray-green foliage and spiny branches, which provide dense shade and cover. Bark is thin and scaly, and leaves are evergreen except during extreme drought or cold.

Ironwood blooms from late spring to early summer, producing abundant clusters of lavender to purplish pea-like flowers, which are highly attractive to pollinators. These blooms are followed by small, bean-like pods that offer an important seasonal food source for wildlife. Its dense canopy creates microhabitats beneath it, nurturing young plants of other species and offering critical shade and shelter in the desert.

Due to its very dense, heavy heartwood, Ironwood has traditionally been used by Native peoples for tools and fuel. Some trees are estimated to be over 1,000 years old, making it one of the oldest desert plants in the region. It is native to well-drained soils along dry washes, alluvial fans, and rocky slopes in low desert habitats, and requires no supplemental water once established. Use it as a structural shade element in desert habitat gardens or naturalistic plantings, with care in placement due to its thorns.

Wildlife Value
Host Plant: Funereal Duskywing (Erynnis funeralis)
Nectar Source: Funereal Duskywing (Erynnis funeralis)
Bird Resources: Seeds; Insects; Shelter; Nest
Bird Species: Gambel’s Quail (Callipepla gambelii); Verdin (Auriparus flaviceps); Gilded Flicker (Colaptes chrysoides); Phainopepla (Phainopepla nitens); Costa’s Hummingbird (Calypte costae)
Other Wildlife: While not a food source for the Desert Tortoise (Gopherus agassizii), this plant provides essential habitat value by offering shade and cover and is commonly used as a site for burrows.

Plant Care

Native region:

Local Native

Water needs:

Low

Exposure:

Full Sun

Mature size:

30'x30'

Growth rate:

Moderate

Flower color:

Purple

Flower season:

Spring - Summer

Pruning:

Prune conservatively to shape, elevate canopy base (crown raise) and remove occasional water sprouts and suckers

Cold Hardiness:

20 Degrees - may lose it's leaves in response to cold

Nectar-producing:

Yes

Attracts pollinators:

Yes

Nighttime pollinators:

Butterflies or Moths:

Yes

Monarchs:

Larval host:

Yes

Bees:

Yes

Bats:

Birds:

Yes

Nest site:

Yes

Nest materials:

Rabbit-resistant:

Yes

Tortoises:

Yes

Growing Plants in the Desert — Important Information

The information presented here is, to the best of my knowledge, accurate and based on reliable research, personal experience in my own garden, observations from other gardens I’ve visited, and time spent studying plants in their native habitats. I always welcome your feedback and experiences to help me continue educating others!

Cacti:
In my experience, cacti are much happier in filtered shade here in the low desert of the Coachella Valley. Their colors are more vibrant and they tend to bloom more profusely, especially the non-native varieties. If you look closely at how our native barrel cactus and beavertail prickly pear grow in the wild, you’ll often find them tucked among rocks or beneath the shelter of creosote and other shrubs.

⚠️ A note of caution: Cacti and succulents are often illegally collected from the wild, which not only damages plant populations but also disturbs entire ecosystems. In some cases, wild populations of cacti have even gone extinct because of this practice. When purchasing these plants, always be sure they’ve been legally obtained. Look for nursery-grown stock or plants with a native plant certification, and keep that documentation for your records.

Light Requirements:
In our desert (Sonoran/Colorado), “full sun” doesn’t always mean what you might think. Many so-called full-sun plants benefit from and actually appreciate some late-afternoon filtered light—especially during the intense summer months.