The United States is one of the world’s largest producers of pistachios. Commercial cultivation of the pistachio tree, Pistacia vera, is highly localized, concentrating in a few arid regions of the Southwest. This geographical focus results from the tree’s unique horticultural needs, which demand a delicate balance of cold winters and intensely hot summers. The US industry has grown significantly since commercial production began in the 1970s, now contributing a substantial portion of the global supply.
California: The Center of US Pistachio Production
California dominates the domestic pistachio industry, accounting for approximately 98% to 99% of all pistachios grown in the United States. The vast majority of this production is centered in the state’s Central Valley, which provides the precise climate necessary for the crop. This area, stretching from Bakersfield in the south to Sacramento in the north, is exceptionally suitable for large-scale pistachio orchards.
The most concentrated production occurs in the southern half of the Central Valley, specifically within the San Joaquin Valley. Five counties—Kern, Madera, Fresno, Kings, and Tulare—are responsible for nearly all of California’s output. Fresno County alone often accounts for about 40% of the entire US pistachio production, highlighting the area’s significance. These counties have the ideal combination of deep, well-draining soils.
Secondary and Emerging Growing States
While California is the leader, commercial pistachio growing extends to a few other states that share a similar arid climate profile. Arizona and New Mexico are the only other states with established, though significantly smaller, commercial operations. Together, these two states produce the remaining 1% of the total US crop.
Arizona has a growing industry that includes close to 10,000 planted acres. New Mexico also hosts commercial orchards, primarily in areas that mimic the climate of the Central Valley, such as the high desert. Plantings have also occurred in far west Texas, where the climate criteria can be met.
Necessary Climate and Soil Conditions
The geographical concentration of pistachio farming is dictated by the tree’s environmental requirements. Pistachio trees demand long, hot, and dry summers, which are necessary for the proper maturation and splitting of the nut kernel. The growing season requires arid conditions to prevent diseases, with kernels developing rapidly from July to early September.
Equally important is the tree’s need for a sufficient period of winter dormancy, which is triggered by a specific number of cold hours. Pistachios typically require approximately 800 to 1,200 hours where temperatures remain below 45°F (7.2°C) to ensure uniform bloom and successful fruit set in the spring.
The trees thrive in deep, well-drained soils and possess a tolerance for high levels of salinity and alkalinity. This makes them well-suited for the naturally drier, salt-rich soils often found across the Southwestern United States.