Arizona AVAs

Sonoita AVA

Established on 25 October 1984, the Sonoita AVA is located in southeast Arizona, south of the city of Tucson. The Sonoita AVA area is a basin surrounded by four mountain ranges, the Huachuca Mountains, the Santa Rita Mountains, the Mustang Mountains, and the Whetstone Mountains. The vineyard plantings are 4,500 to 5,000 feet above sea level, some of the highest in North America.

Sonoita AVA takes its name from a small town at the center of the AVA, 20 miles west of the larger town of Sierra Vista and 40 miles south-east of Tucson. On a wider scale, Sonoita AVA's location lies roughly between the Santa Cruz and San Pedro rivers, 20 miles north of the Mexican border.

The altitude here is between 4000 and 5000ft, 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 AVA's terroir.  By being removed from the heat endured on the plains, Sonoita AVA has a longer growing season, during which the grapes are given time to develop high levels of phenolic ripeness.

Because of Sonoita AVA'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.

A wide variety of grapes, from the warmer climate varieties of Cabernet Sauvignon and Merlot, to the cooler site Pinot Noir and Sauvignon Blanc, are grown in Sonoita AVA.

The Sonoita AVA is one of these locations where producers are turning out quality wines in the style of the warmer European regions such as France's Southern Rhône Valley.

Nearest Large Cities

Tucson

Nearest Airports

TUS
Tucson International Airport

Verde Valley AVA

Established on 9 November 2021, the Verde Valley AVA, is approximately 200 square-mile in size and located in Yavapai County, Arizona.  The Verde Valley AVA is approximately 100 miles north of the Phoenix metropolitan area.  The Verde River flows through the center of the valley from northwest to southeast, and steep foothills rise up around the valley. 

The entire geological feature known as the ‘‘Verde Valley’’ encompasses approximately 714 square miles, most of which is National Forest land and unavailable for viticulture.  Although an effort was made to exclude as many public lands from the Verde Valley AVA as possible, approximately 33 percent of the land within the Verde Valley AVA is still part of either the Prescott or Coconino National Forests. It was not practical to draw a boundary that would exclude all Federal land because several of the vineyards within the Verde Valley AVA are ‘‘islands’’ of private land surrounded on all sides by Federal land. Even with the amount of Federal land remaining within the AVA, there is still plenty of privately owned land available for vineyards within the boundaries. The Verde Valley AVA currently has approximately 160 acres under vine.

The Verde Valley AVA is located within the basin of the Verde River. The shape of this basin has been described as a ‘‘bowl with a crack in it to the south where the river flows out of the valley.’’ The edges of the ‘‘bowl’’ gently slope down towards the valley floor at angles of 2 to 15 percent. Elevations within the AVA range from approximately 3,000 feet to 5,000 feet, although most of the AVA is below 3,800 feet.

The AVA is surrounded on all sides by higher elevations and steeper slopes. To the north and northeast of the AVA, elevations rise up to 8,000 feet along the edge of the Mogollon Rim. To the west and southwest of the AVA are the Black Hills, which have steep slopes and elevations up to approximately 7,800 feet. 

The Verde Valley AVA’s topography affects the viticulture.  Gentle slopes allow for easier vineyard management than steep slopes. Furthermore, because the AVA is lower than the surrounding regions, cold air drains from the higher elevations into the AVA during the spring and fall.  As a result, the risk of frost damage increases in the AVA, particularly in vineyards adjacent to the river and the river’s numerous tributary creeks flowing from the north. Vineyard owners mitigate the risk of frost by using inversion fans and protective sprays and by planting late-budding varietals of grapes.

Average annual rainfall amounts within the Verde Valley AVA are significantly lower than in the surrounding regions.  Due to the low rainfall amounts, vineyard owners within the AVA must use irrigation to ensure adequate hydration for their vines. There are sufficient sources of groundwater within the AVA for irrigation, and vineyard owners employ water conservation methods such as drip irrigation and the use of agriculturally approved reclaimed water.

While cooler than the lower Arizona deserts, temperatures within the Verde Valley AVA are warmer than in each of the surrounding regions and provide suitable heat and sunlight for photosynthesis. The warm daytime temperatures lead to high annual GDD accumulations.

The difference between the daytime high temperatures and nighttime low temperatures within the AVA, known as ‘‘diurnal temperature swings,’’ are substantial and can exceed 30 degrees F, which is a greater difference than found in any of the surrounding regions. Such a significant drop in nighttime temperatures delays grape ripening, lessens the respiration of acids, and increases phenolic development in the grapes.

The soils within the Verde Valley AVA are primarily alluvial soils.  The composition of these soils ranges from very fine sandy loam to gravelly loam with silt and limestone.  Traces of the Supai, Verde, and Martin Limestone formations can also be found throughout the AVA.

The soils of the AVA generally provide appropriate water drainage and have above-moderate levels of nutrients, although low calcium and magnesium levels are common. Additionally, high bicarbonate levels in the groundwater of the AVA have been found to increase soil pH and inhibit nutrient uptake in the vines. These unfavorable vineyard conditions can be mitigated through rootstock, varietal, and clonal selections that can tolerate and even benefit from these nutrient deficiencies.

The temperatures and GDD accumulations within the AVA are well suited for growing warm climate grapes such as Syrah, Cabernet Sauvignon, Petite Sirah, Zinfandel, Malvasia Bianca, and Viognier.

Nearest Large Cities

Phoenix
Flagstaff

Nearest Airports

PHX
Phoenix Sky Harbor International Airport

FLG
Flagstaff Pulliam Airport

Willcox AVA

Established on 11 September 2016, the Willcox AVA is located in southeastern Arizona and covers an area in northern Cochise and southern Graham counties along the northern part of Sulphur Springs Valley.  The Wilcox AVA is centered around the city of Willcox where it is bisected by Interstate 10.  Approximately 80-85% of wine grapes from Arizona are grown within the Willcox AVA boundaries.  The Willcox AVA covers an area of about 833 square miles. About 582 square miles (70%) of the Willcox AVA is privately owned land. Federal and state entities manage the remainder.

The Willcox AVA consists mostly of flat terrain at over 4,000 feet in elevation, including the Aravaipa Valley and much of Sulphur Springs Valley. It is bounded by the Chiricahua Mountains and Dos Cabezas Mountains to the east, the Pinaleño Mountains to the northeast, and the Dragoon Mountains to the west. Sixty miles to the southwest is the Sonoita AVA, and the Mimbres Valley AVA is 120 miles to the east in New Mexico. The Willcox AVA is one of the three major centers of viticulture in Arizona, along with Sonoita AVA and the Verde Valley AVA in central Arizona. 

Much of the Willcox AVA has a Growing Season Temperature between 66°F and 70°F. Isolated areas and the southwestern part are warmer and have long-term normal values between 70°F and 75°F.  Much of the central part of the Willcox AVA from northwest to southeast has an average date of the last spring freeze during the second half of April.  Many areas along the Willcox AVA boundary have dates during the first half of April.  Freezing temperatures close to the start of the growing season can damage vines and reduce yield.

Much of the central part of the Willcox AVA from northwest to southeast has an average date of the first fall freeze during the second half of October.  Many areas along the Willcox AVA boundary have dates during the first half of November.  Freezing temperatures close to the end of the growing season can damage vines and unharvested fruit, as well as curtail post-harvest photosynthesis and carbohydrate accumulation.

Igneous rock is a known parent material occurring in areas throughout the Willcox AVA. Limestone appears along the eastern, southern, and southwestern AVA boundaries. Mixed parent material also appears along the southern and southwestern boundaries.  Parent material is the type of bedrock from which soil forms. As a component of vineyard soils, it influences water infiltration, storage, and drainage, erodibility, pH, nutrient availability, and heat absorption, which affect root, canopy, and fruit growth.

Sand and gravel are the most abundant rock types for almost all of the Willcox AVA. Dacite, rhyolite, granodiorite, granite, conglomerate, and sandstone occur in isolated areas close to the southern boundary.  Known depths to bedrock are less than 12 inches for areas in the central part and along the northern and southern boundaries of the Willcox AVA. Depths between 24 and 36 inches exist in the north-central part.  Depth to bedrock represents the distance from the soil surface to the top of a restrictive layer, such as bedrock and other dense layers. As a component of vineyard soils, such restrictive layers can impede water drainage and restrict root depth.

For much of the Willcox AVA, soil texture is fine sandy loam, loam, sandy clay loam, sandy loam, silt loam, and silty clay loam. Areas of sand, coarse sand, loamy sand, and loamy fine sand occur throughout the AVA, as do areas of clay and silty clay along the western and southern boundaries.  Much of the Willcox AVA has well-drained soils.  Excessively, somewhat excessively, moderately well, and somewhat poorly drained soils occur near the Willcox Playa. An area of somewhat poorly and poorly drained soils exists in the southeastern part of the AVA, and an area of somewhat excessively drained soil exists in the northern part.

Many areas in the Willcox AVA have available water storage in the top approximately 40 inches of soil greater than four inches. Areas with values between three and four inches occur throughout the AVA, and those with values less than three inches exist in the central and extreme south-central parts of the AVA.

Soil pH is between 8 and 9 across much of the central part of the Willcox AVA, particularly to the north and south of the Willcox Playa. Much of the rest of the AVA has soil pH between 7 and 8. Soil pH for some areas along the AVA boundaries are between 6 and 7.

Approximately 1,100 acres are planted with grape vines.  A range of grapes are grown in the area, with a major nod to Bordeaux and Mediterranean varieties. Some of the stars of the region seem to be Viognier, Tempranillo, and Mourvèdre.

Nearest Large Cities

Tucson

Nearest Airports

TUS
Tucson International Airport