How Do Pistachios Grow? Only in These Growing Zones (Pistachio Tree Guide)

The seed of the Pistachio Tree is one of the world’s most delicious (and most expensive!) nuts, and many gardeners are asking “how do Pistachios grow?”

However, the Pistachio Tree is fairly limited in where it likes to grow, requiring hot and dry environments, but it does very well within its preferred climates.

This Pistachio Tree guide has all the information a Pistachio lover needs to know about the beloved nut and its growing habits.

Image Credit: reklam43⁴⁵

What Is the Pistacia vera Tree?

Pistacia vera is a species of small fruit-bearing tree native to southwestern Asia (Middle East) which is a member of the cashew family (Anacardiaceae).³⁹ It thrives in hot, dry climates and produces a small drupe fruit with a red-gold, thin fleshy hull around the hard inner husk when it matures.

As the growing season progresses, the seed grows to fill the husk, typically creating a partial split in the husk. The seed within the husk is the popular Pistachio nut which is grown commercially in the Middle East and the U.S. and eaten around the world.

(Image: hosein.fa⁴⁴)

Pistachios are often sold inside the shell as the split allows consumers to shell the nut themselves. These ‘nuts’ have become a staple in many popular dessert dishes, and their healthy fats are known to lower the risk of heart disease.²

According to the International Union for Conservation of Nature and Natural Resources (IUCN), Pistacia vera is considered “Near Threatened” with populations decreasing.^{16, 39}

How Many Types of Pistachio Tree Are There?

Pistacia vera is not the only species of Pistacia extant in the world.^{39, 43} However, it is the only species that bears fruit large enough for commercial production and consumption.

The many other Pistacia species are used for various purposes,⁴³ such as in carpentry, for rootstocks, and for oil.¹¹ There are 11 other accepted Pistacia members, including:^{24, 43}

• Pistacia aethiopica³⁷
• Pistacia atlantica (Mt. Atlas Mastic Tree, Atlas Pistachio)²⁹
• Pistacia chinensis (Chinese Pistache)³¹
• Pistacia eurycarpa (Persian Turpentine Tree)³⁶
• Pistacia falcata³³
• Pistacia khinjuk³²
• Pistacia lentiscus²⁷
• Pistacia mexicana (Mexican Pistache, American Pistachio)³⁰
• Pistacia terebinthus (Terebinth, Turpentine Tree)²⁸
• Pistacia weinmanniifolia³⁴
• Pistacia x saportae (Hybrid Mastic Tree)³⁵

11 Pistachio Tree Facts (How Do Pistachios Grow)

The pistachio tree has a fascinating cultural and economic history dating back much further than most consumers realize. There are so many interesting Pistachio Tree facts to explore, and this section looks at eleven facts that set this nut apart from other nut varieties.

1. The composition of the Pistachio nut is approximately 45.3% fat (23.3% monounsaturated fatty acids, 14.4% polyunsaturated fatty acids, 5.9% saturated fatty acids), 27.2% carbohydrates (10.6% fiber, 7.7% sugar, 1.7% starch), and 20.2% protein.¹¹
2. The Pistachio is in the same plant family as Poison Ivy, Cashews, and Mangoes.¹¹
3. Pistacia vera is the only Pistacia species grown as a commercial food source.^{11, 39, 43}
4. There is some evidence to suggest that the Pistachio nut was actually one component of the Neanderthal diet.¹¹
5. The Pistachio is one of only two nuts mentioned in the Bible.¹¹
6. The United States now produces nearly 50% of Pistachios worldwide, with 99% of U.S. Pistachio production occurring in southern California.¹¹
7. Pistachios usually reach peak production at around 15 years,¹¹ but a 10 year old tree can produce between 25 and 100 lbs of nuts.²⁰
8. Pistachios operate on a biennial schedule, alternating between high and low production each year.¹¹
9. Pistachio Trees are actually grown by grafting a Pistacia vera cutting onto the rootstock of another Pistacia species,^{39, 43} usually, P. atlantica or P, terebinthus.
10. Pistachio shells are toxic to canines.²
11. Female Pistachio Trees are commonly called ‘Kermans’ and males are commonly called ‘Peters’ or ‘Randy’.¹⁵

Read More: How Much CO₂ Does a Tree Absorb?

What Are Red Pistachios?

Red Pistachios are not a unique Pistacia species. In fact, red coloring was an artificial dye commonly used during the 1960s and 1970s to distinguish certain producers’ stock and disguise shell stains.

(Image: reklam43⁴⁵)

Red Pistachios became a common sight in the U.S. as more and more Pistachio imports from Iran bore the signature red dye. However, tension between the U.S. and Iran led to a halt on trade between the two countries, and the U.S. began producing its own dye-free Pistachio crops.⁷

Why Were Pistachios Dyed Red?

Many people who have long been accustomed to the tan husks of the Pistachio may remember a time when the shells were artificially colored and wonder “Why were Pistachios dyed red?” The quick answer is that Pistachio shells absorb color and stains from the thin, red-gold hulls if they are not processed quickly,¹¹ and shell dying served the very practical purpose of hiding and disguising this discoloration.

The practice of dying Pistachios red may also have begun as a way to distinguish a particular seller’s, grower’s or area’s produce.⁷

Why Are Pistachios So Expensive?

Nuts are some of the healthiest snacks people can eat, but sometimes the cost can be prohibitive, leaving many to wonder “Why are Pistachios so expensive?” Although Pistachios are not the most expensive, they are quite pricey, and this is due to several factors, including:

• The limited areas where they can be grown
• The length of time it takes a tree to yield a significant crop
• The alternate bearing pattern of the trees (one year on, one year off)
• The labor and time required to harvest and process ripe Pistachios¹³

What Does a Pistachio Tree Look Like?

The vast majority of people have probably eaten a Pistachio nut at some point in their lives, but most of those same people would be at a loss to answer “What does a Pistachio tree look like?”

The Pistachio tree is a smaller tree, capping out at around 30 ft. in height, with branches spreading as wide as its height.²⁰ It is deciduous, so its leaves change colors in the autumn and fall to the ground in the winter.

The Pistachio may grow as a large shrub, but careful pruning usually forms it into a fairly erect tree with a rounded canopy.

Pistachio Tree Leaves

Pistachio tree leaves are pinnately compound and arranged in an alternating pattern. Each leaf usually bears about 5 to 7 oval-shaped leaflets.

The thick, leathery leaves are often blue-green or gray-green in the summer and turn to a brilliant red in the autumn.²¹

Pistachio Tree Flower

Pistachio tree flower are very small and inconspicuous. The individual flowers are unisexual, meaning that male and female flowers grow on different plants.

The flowers lack petals, but they form attractive red clusters in the springtime.¹⁴

Pistachio Tree Seeds

Pistachio tree seeds are commonly referred to as a ‘nut’ although they are not a true nut. The seeds are encased in beautiful, red-gold, oval-shaped, drupes which appear in the fall.

The drupes gradually dry until ripe. The outer fleshy hull must be cleared away to reveal the hard, inner husk.

When ripe, Pistachio husks (shells) usually develop a partial split which allows the tasty seed to be removed. The seed itself is dry, ovoid, and green to brown, with a somewhat crumpled appearance.⁸

Planting Tips for Pistachio Tree (How Do Pistachios Grow?)

Planting Pistachios is one of the trickiest parts of growing this species. The process is quite unique, and planting tips for Pistachio trees abound on the internet as people search for information on how do Pistachios grow.

The Pistachio is usually propagated by budding or grafting onto a rootstock, and transplanted trees can bear fruit as soon as four years from grafting, with significant yield at 8+ years.²⁰ However, first-time Pistachio growers are likely to have less success grafting and budding and may want to try their hand at growing from seed or seedlings.

Growing Pistachio Tree From a Seed

Growing Pistachio Tree from a seed is not generally recommended as the grower cannot control whether the resulting tree will be male or female. Commercially, Pistacia vera is grafted to the rootstock of a hardier Pistacia species,^{39, 43} such as Pistacia atlantica or Pistacia terebinthus, and specific male or female graftings are selected.^{28, 29}

Much like learning how to grow Mango Tree from seed, there are many steps to follow to grow a successful Pistachio Tree. To begin, the raw seeds must be stratified by soaking in cool water for 3 hours.

They must then be placed in a container of sand and peat moss and stored for 6 weeks in the refrigerator. Once the seeds have germinated, they should be transitioned to peat pellets and put in a sunny location.

They can be moved to containers when they outgrow the pellets and transferred outside in the early spring when their roots fill a 1.5 ft. deep container.⁸

Growing a Pistachio Tree From a Seedling

Growing a Pistachio Tree from a seedling is quite a bit simpler than starting from seed. Seedlings are usually purchased pre-potted.

The most important component is keeping the seedlings well-lit and moist. The Pistachio Tree does best with minimum disturbance, so some seedling may come in paper containers which break down after planting.

Transplant the seedling outdoors in the early spring and keep it well-watered. The first 18 inches of growth should be a single trunk, but lateral branches beyond that are retained for nutrient uptake.⁸

Growing a Pistachio Tree From a Cutting

Growing a Pistachio Tree from a cutting is not impossible, but it is also not advised, as such specimens have typically performed poorly.¹⁹ To grow from a cutting, the cuttings must come from a healthy tree and placed in a rooting hormone before planting in moist but well-draining potting mix.

If watered and well-lit, the Pistachio cuttings can take root within a few months, allowing for transplant the following season.⁹

When To Plant Pistachio Tree for the Best Yield?

Pistachio Trees usually do not produce fruit until around 4 to 5 years post-grafting, so the topic of when to plant Pistachio Tree for the best yield is a bit misleading.

However, beginning Pistachio Trees in the spring allows them to settle in and become established over the summer.

How Far Apart To Plant Pistachio Tree?

Figuring out how far apart to plant Pistachio Trees is central to growing a successful orchard.

The best arrangement for a grove of Pistachio Trees is to plant the larger male tree in the center of six to ten female trees at a distance of 25 to 30 feet apart.²⁰

Individual trees may be planted 12 feet apart with 24 feet between rows. The spacing is super important because Pistachio Trees do not tolerate shade.

A grid arrangement with every male tree surrounded by eight female trees in a square has demonstrated success.⁸

Best Growing Conditions for Pistachio Tree (How Do Pistachios Grow Best?)

The best growing conditions for Pistachio Trees are in open areas with full sun. Pistachio Trees thrive in arid climates with:

• Low humidity
• Dry to moist
• Well-draining soil
• Long hot summers
• Moderately cold winters¹⁰

Pistachio crops grown in the U.S. are usually harvested during the early fall (August and September) at the end of the long growing season of more than 600 hot hours (> 86°F). Then, they require approximately 1,000 chilling hours (< 45°F) throughout the winter.¹¹

Gardeners who want more information on how do Pistachios grow best should continue reading in the following sections!

Growing Zones for Pistachio Tree (Where To Grow)

Unlike the Cashew Tree which thrives in semi-tropical, humid environments, the Pistachio Tree prefers dry, arid climates.²⁰ Curious about growing zones for Pistachio Tree?

Where to grow Pistacia vera is a piece of information essential to having a successful Pistachio crop.³⁹

The ideal growing zones for Pistachio are zones 8 to 10, though Pistachios can also thrive in hotter areas of 7b and drier areas of 11a (see USDA Plant Hardiness Zone Map).³⁸

In the United States, the southernmost areas of California, New Mexico, and Arizona are the climates best suited to Pistachio growing.

How Much Sunlight Does Pistachio Tree Need Each Day?

One important question to explore when venturing into Pistachio growing is “How much sunlight does Pistachio Tree need each day?” The answer is a lot.

Pistachios do not tolerate shade. They must be adequately spaced when planting groves or orchards to prevent one tree from shading out another.

Pistachios thrive in open spaces where they can receive full sun throughout each day of the hot growing season.

Watering Needs for Pistachio Plants

The watering needs for Pistachio Plants are low maintenance, particularly once the tree is established. Young trees (less than 5 years) require up to 50 gallons per day during the hottest months of the growing season, and drip irrigation systems are ideal for achieving this.

Established orchards can tolerate extended periods of drought.¹⁸

How Long It Takes To Grow Pistachio Tree?

Many people who love the idea of growing their own Pistachios may be discouraged by how long it takes to grow Pistachio Trees. Pistachio Trees take 5 to 6 years to become decently well-established.

This is also the approximate amount of time they need to begin bearing fruit. However, Pistachio Trees won’t reach peak production until they are between 10 and 15 years old, and then they only produce maximally every other year on an alternate-bearing schedule.¹⁸

In other words, cultivating Pistachios is a lengthy process that could very well be a lifelong adventure for some.

Companion Plants for Growing Pistachio Tree

The Pistachio Tree is wind-pollinated, so attracting pollinators such as bees and butterflies is not a concern when exploring companion plants for growing Pistachio Trees. In fact, as long as both male and female trees are growing in the same area, the Pistachio is fairly self-sufficient.

The primary concern when selecting companion plants is ensuring that those plants do not grow larger than the Pistachio or create too much shade. As the Pistachio grows a broad canopy, any companion plants will need to be shade tolerant.

They must also be tolerant of the dry weather and soils that the Pistachio Tree prefers.¹⁵ Other types of trees, such as the American Hazelnut Tree and Almond Tree grow in similar environments.

Common Pests of the Pistachio Tree

The Pistachio tree is fairly pest resistant, and the most common pests of the Pistachio Tree are insects such as aphids and stink bugs, and birds. However, the most problematic pest is the Navel Orangeworm.¹⁵

The Navel Orangeworm (Amyelois transitella) is a small,¹² grayish black moth which deposits eggs on the fruit of trees such as Pistachio and almond. The larvae bore into the nut over time and can even survive through winter in “mummy” nuts.

This insect can cause significant damage to the trees and fruit by introducing fungus.¹²

Natural Pest Control for Pistachio Tree

The University of California Agriculture & Natural Resources Statewide Integrated Pest Management Program (UC IPM) provides specific and useful information on dealing with a variety of Pistachio pests,⁴⁰ but many of their guidelines involve the use of insecticides, miticides, and pesticides.

The best natural pest control for Pistachio Trees involves harvesting ripe nuts early and clearing nuts from the ground, destroying/removing “mummy” nuts in the fall to eliminate any wintering larvae, and sanitizing harvesting tools and equipment before moving from one orchard to another.¹²

The USDA’s Plant Protection and Quarantine (PPQ) program has been experimenting with introducing sterile Navel Orangeworm populations to almond and Pistachio orchards in California in the hopes of protecting these valuable crops.^{5, 41}

Pistachio Tree Disease Prevention

Pistachio Tree disease prevention is primarily conducted by using hardy rootstocks from different Pistacia species and grafting Pistacia vera to these rootstocks.^{43, 39}

In this way, commercial growers have been able to produce Pistachio orchards which are more tolerant of the cold and more disease and rot-resistant.

However, sometimes a Pistachio Tree still succumbs to disease. Continue reading for advice on what to do when this happens.

How To Stop Pistachio Tree Disease

UC IPM also provides useful information on how to stop Pistachio Tree disease.⁴⁰ Verticillium wilt (Verticillium dahliae) is probably the most problematic for Pistachio Trees,²⁵ as this disease cannot be effectively treated with fungicides.

Verticillium wilt may desiccate a tree quickly or cause a gradual decline over time. The fungus affects the soil around the root system and attacks the roots.

The most resistant rootstock to use is that of Pistacia integerrima, as it is less susceptible to V. dahliae than P. atlantica and P. terebinthus.²⁵

Soil solarization has been noted to temporarily stall the disease, as Verticillium wilt thrives in cooler conditions, but in most cases, removal of infected trees is required.

(Image: Alexas_Fotos⁴⁶)

To grow a Pistachio Tree, an individual must do a lot of research in advance. From learning where to plant it, how to graft it, and how to nurture young trees, Pistachio growing can be a bit of a learning curve.

However, for individuals living in zones 8 through 10, growing Pistachios can also be a very fulfilling adventure.

Use this Pistachio Tree guide for many tips on how do Pistachios grow.

Frequently Asked Questions About How Do Pistachios Grow