“Arizona-found seedling from the Aravaipa Valley — 'doesn't need protection.' The desert avocado experiment.”
Background
A local Arizona seedling selection, not a commercial cultivar. The mother tree stands on a private ranch in Aravaipa Canyon, northeast of Tucson, and is reported to be roughly 50 feet tall and over 100 years old, surviving desert extremes unprotected. Seedling material circulates among Arizona rare-fruit growers; documentation is anecdotal rather than published. The UA arboretum notes avocado has been a dietary staple for over 9,000 years, cultivated since around 8000 BCE, with its name from the Nahuatl 'ahuacatl.'
Distinguishing traits
Exceptional cold tolerance (reportedly down to about 14-18°F) and heat tolerance (reportedly to 120°F). Guatemalan/Mexican seedling heritage; flower type is reported as Type A by some growers and Type B by others, so this is unresolved in the documentation. Fruit quality is thinly documented; one source describes the flavor as similar to Hass. Sourcing is thin: availability is sporadic and local. The UA arboretum describes avocado as a low-branching evergreen tree with leathery, anise-scented leaves and large clusters of greenish-yellow winter flowers.
Desert care — zone 9b
- Chill hours
- Not a limiting factor for avocados in the low desert.
- Cold hardiness
- Reported hardy to about 14-18°F once established, among the hardiest avocados known; this is the cultivar's main claim to fame. The UA arboretum gives USDA zones 9a-10b (20-35°F), noting frost tolerance varies by race: Mexican types to 20°F, Guatemalan to 28°F, West Indian to 32°F.
- Heat tolerance
- Reported to tolerate 120°F; however, like all avocados, young trees should be protected from sunburn on trunks and branches with shade or white paint.
- Water
- Deep, regular watering; avocados are salt-sensitive, and Arizona soils and water can be salty, so occasional deep flushing helps. The UA arboretum rates water use as moderate and recommends well-draining, aerated, high-organic soil around pH 5-5.8.
- Soil
- Fast-draining soil; avoid heavy clay and caliche. Planting on the east side of a larger tree gives summer afternoon relief.
- Sun exposure
- Full winter sun, but protect young trees from harsh summer afternoon sun; afternoon shade cloth is prudent during establishment.
Where to buy
- Shamus O'Leary's Tropical Fruit Trees (Glendale, AZ; sporadic local availability, verified via grower forum)