Arizona · Est. 1924
Boyce Thompson Arboretum
Arizona's oldest and largest botanical garden, featuring diverse arid-land plants from around the world.
Founded
1924
Size
392 acres
Hardiness Zone
USDA Zone 9a
Best Season
March to May for spring blooms and pleasant weather.
About Boyce Thompson Arboretum
Boyce Thompson Arboretum is the oldest and largest botanical garden in Arizona, located in the Sonoran Desert beneath Picketpost Mountain. It spans 392 acres and features over 4,000 taxa of arid-land plants from various global regions. The arboretum serves as a living museum and research facility, inspiring appreciation and stewardship of desert ecosystems.
History & Heritage
Founded in 1924 by mining magnate William Boyce Thompson, the arboretum was established as a desert plant research facility. It became Arizona's first non-profit research institution in 1927 and opened to the public in 1929. In 1976, it was listed on the National Register of Historic Places and entered a Tri-Partite Agreement to become a state park while remaining a scientific research facility.
Signature Feature
Mr. Big
Mr. Big is a massive Red River Gum eucalyptus tree and an Arizona Champion Tree. It is a prominent feature of the arboretum's nationally accredited eucalyptus collection, which includes many trees planted in the 1920s.
Photo Gallery
A butterfly on a flower at Boyce Thompson Arboretum.
A pink rose blooming in the gardens.
Saguaro cacti in the Sonoran Desert landscape.
Notable Collections
Eucalyptus Collection
A nationally accredited collection featuring 93 taxa, including the massive 'Mr. Big' Red River Gum.
Desert Legume Collection
An internationally recognized, seed-based collection of desert legumes, with 121 species grown in field plantings.
Oak Collection
A nationally accredited collection of oak trees sourced from the southwestern United States and northern Mexico.
Australian Deserts Exhibit
One of the largest collections of Australian plants in the U.S., featuring eucalyptus, acacia, and melaleuca species.
Recognition & Awards
- National Register of Historic Places
- Audubon Important Bird Area
Editorial Standards
This profile was researched and written by the BotanicalGardens.blog editorial team, which includes certified Master Gardeners and horticultural writers with field experience across the United States. All admission prices, hours, and garden details are verified against official garden websites and updated May 2026. If you notice an inaccuracy, please contact us.
Plan Your Visit
March to May for spring blooms and pleasant weather.
Address
37615 E. Arboretum Way, Superior, AZ 85173
Phone
(520) 689-2723
Hours
Oct-Mar: 8am-5pm daily; Apr: 7am-5pm daily; May: 6am-3pm Mon-Fri, 6am-5pm Sat-Sun; Jun-Aug: 6am-12pm Wed-Mon; Sep: 6am-3pm Wed-Mon
Admission
Adults: $24.95, Youth (13-17): $24.95, Children (5-12): $10, Members & Children under 5: Free
Insider Tips
- 1Bring a hat, sunscreen, and plenty of water, as the arboretum is in the Sonoran Desert.
- 2Wear long pants and closed-toed shoes for exploring the unpaved trails.
- 3Leashed and well-behaved pets are welcome at no additional cost.
- 4Allow at least two hours to explore the 4.5 miles of trails and 135 acres of gardens.
Nearby Attractions
- Picketpost Mountain Trail (3 miles)
- Main Street Superior (3 miles)
- Legends of Superior Trail (LOST) (3 miles)