Pistachio nuts are getting a lot of press these days. Not only are they the lowest calorie of the nuts, but they are rich in phytosterols, antioxidants, unsaturated fat (the good stuff), carotenoids, vitamins and minerals, fiber and are just plain delicious. If that isn’t enough information to entice one to grow pistachio nut trees, I don’t know what will.
There are 11 species of pistachio nut trees with only Pistacia vera being grown commercially. It’s uncertain where pistachio nut trees originated, but possibly in Central Asia. Growing pistachio trees commercially for nut export occurs primarily in Turkey, Iran, Afghanistan, Italy and Syria where the arid climate is optimal for growth.
Climate is crucial when growing pistachio trees; ideal temperatures for pistachios are above 100 F (38 C) during the day. Pistachios also need winter months cold enough to complete their dormant period — 45 F (7 C) or below. In addition, pistachio nut trees don’t do well at high elevations due to the cool temps, or anywhere where it dips below 15 F (-9 C).
So it’s a little picky about its temperature requirements. Conversely, pistachio trees do well in all soil types but really thrive in deep sandy loam. Well draining soil is a must and infrequent deep irrigation if possible. Additionally, they are quite drought tolerant but don’t do well in areas of high humidity.
Although pistachio trees are long living, with a large tap root, and can grow to 20-30 feet (6-10 m.) seedlings can be grown in containers for the first three to five years and then transplanted into the garden. In the garden or orchard, trees should be planted 20 feet (6 m.) apart. Pistachio nut trees are dioecious; therefore, to get good crop set, both male and female trees are needed.
Pollination is through wind dispersal of pollen, which usually takes place in early to mid April. Stormy springs may affect the crop set by interfering with pollination.
Since these trees are classified as fruit trees, pruning pistachio trees is integral to producing higher quality fruit while controlling growth. For young trees, select the three to five branches you wish to use as scaffold branches or the primary structure of your pistachio in April of the first growth season. Choose those that are equally spaced around the trunk but not across from each other with the lowest branch 24-32 inches (61-81 cm.) above the soil and cut all other branches below this.
Remove any upper branches that will shade the tree trunk and pinch those that are not scaffolds to 4-6 inches from the trunk. Then in June, prune the scaffold branches to 2-3 feet (61-91 cm.) in length to promote side branching, while leaving the lateral shoots to aid in shading the trunk as it grows.
Maintain the open center structure as the tree grows taller by choosing secondary scaffold branches. You may prune two to three times a year, with summer pruning occurring in the spring and summer and dormant pruning in the fall.
Nuts for nuts but not crazy for calories? Grow pistachios for a continuing supply of nutrition-packed nuts with a reasonable 160 calories per ounce. Given the right USDA zone, climate and growing conditions, pistachio trees produce up to 50 pounds of nuts per crop. We examine where and how low-maintenance pistachios grow and whether they’ll thrive in your part of the world.
Expert gardener’s tips:
Pistachios’ love for hot, dry summers makes them ideal for desert gardens and orchards, but only in USDA plant hardiness zones where:
These climate requirements limit pistachio growing to the driest parts of USDA zones 7b (a winter low of 5°F) through 10b (with winter lows between 35 and 40°F).
Although pistachios accept infertile, rocky or even salty soil, they produce most heavily in deep, well-draining sandy loam. For the healthiest trees, aim for slightly alkaline soil with a pH in the 7.1 to 7.8 range. The best site also has little or no shade.
Plant 1-year-old pistachio trees in January or February. Dig holes deep enough to contain their roots without bending. Allow 15 to 18 feet between individual trees and 20 to 22 feet between orchard rows. Water thoroughly after planting.
Expert gardener’s tip: Always plant compatible cultivars. Good pairings include female ‘Kerman’ with male ‘Peters’ pistachios and male ‘Randy’ with female ‘Golden Hills.’
Water your trees infrequently and deeply. Insert a screwdriver 8 inches into the soil near the rootballs if the soil is crumbly and dry, water with a soaker hose or garden hose set to a trickle. Stop in October when pistachios enter winter dormancy.
To prevent mineral deficiency, treat the trees with a foliar spray containing zinc, boron and copper. Spray every three weeks for their first three years.
If the climate is right, there is very little care that a pistachio tree needs to thrive and produce well for decades.
Last Updated: July 24, 2019 References
This article was co-authored by Lauren Kurtz. Lauren Kurtz is a Naturalist and Horticultural Specialist. Lauren has worked for Aurora, Colorado managing the Water-Wise Garden at Aurora Municipal Center for the Water Conservation Department. She earned a BA in Environmental and Sustainability Studies from Western Michigan University in 2014.
There are 13 references cited in this article, which can be found at the bottom of the page.
This article has been viewed 48,474 times.
Growing pistachios is a long term process and requires patience. Pistachio trees only start to bear fruit when they’re about eight years old, and a full harvest will only come fifteen years into the tree’s life. If you have the patience, it’s possible to grow your own pistachios. The trees thrive in hot, dry climates. You’ll have to start with germinating seeds and growing pistachio trees before you can harvest pistachios. You can also buy grafted saplings rather than taking the time to germinate seeds.
Technically, the crop produced by almond trees is not a nut, but a stone fruit (drupe). The fruit growing on almond trees initially looks nothing like the almond you later end up eating: Instead, what you see is a leathery, green hull. Inside the hull is a hard, light-colored shell. This is the shell that we crack with a nutcracker to get at the edible part. Cracking the shell frees the brown seed ("nut") that we eat.
There are different types of almonds. The kind found in nut bowls and dessert recipes is the sweet almond (Prunus dulcis), but there is also a bitter almond (Prunus dulcis var. amara) that is used, for example, to flavor certain liqueurs.
For the most part, almond trees are not self-fertile, as are some trees that bear edible fruit: You will need two or more cultivars for pollination, and they can't be just any cultivars (flowering times have to line up). This is the trickiest part of growing almond trees for a crop of nuts. Plant your almond trees 15 to 25 feet apart from one another.
A smart way to avoid having to plant different cultivars for pollination purposes is to select one of the self-fertile types. For example, 'Garden Prince' is a self-pollinating kind of almond tree that becomes 10 to 12 feet tall it is cold-hardy only to zone 8, though.
Almonds give you a clue as to when they are ready to be harvested: The hulls begin to split apart, revealing the familiar, light-colored shell. Do not wait too long after this splitting to harvest your almond nuts because the exposed shell is now fair game to both birds and insects.
The easiest way to get the almonds off the tree for the home grower is to tap the branches with a pole. Lay a tarp down ahead of time to catch the almonds as they fall to make pick-up easier.
After gathering the almonds, they must be dried properly, else they can become moldy. Drying requires several steps: