Sonoita is an AVA in the south-eastern corner of Arizona, in the south-western United States of America. It is Arizona's only AVA and covers a large area of 28,000 acres (11,300 hectares), taking in the valley basin encircled by the Santa Rita, Huachuca and Whetstone mountain ranges.
Sonoita takes its name from a small town at the centre of the AVA, 20 miles (32km) west of the larger town of Sierra Vista and 40 miles (64km) south-east of Tucson. On a wider scale, Sonoita's location lies roughly between the Santa Cruz and San Pedro rivers, 20 miles (30km) north of the Mexican border.
One of the first AVAs granted in the USA - it was established in October 1984 - it remains, however, Arizona's only designated vineyard area within the wider boundaries of the state itself.
The altitude here is between 4000 and 5000ft (1220–1525m), and the temperatures are correspondingly lower than on the dry plains further down. It is the combination of intense sunshine and moderated temperatures which lies behind the quality of Sonoita's terroir.
Because of Sonoita's foot-of-the-mountain location, the soils are a mixture of igneous rock types, which have made their way downhill over the millennia, and sedimentary types, which have been deposited in alluvial fans. Due to high deposition rates, the Sonoita soils are deep and rich in minerals but are also highly porous.
The fast drainage efficiency which results from this porosity creates good conditions for quality viticulture; waterlogged or slow-draining soils not only pose the risk of 'wet feet', but also remove the incentive for vines to create strong root systems.