The Pistachio tree is a shrub that belongs to the family of Anacardiaceae. Genre pistachio has twelve species, all slow growing. We mainly cultivate pistachio vera as much for the beauty of its foliage as, of course, to be able to harvest its delicious almonds. More specifically, these are pistachios, very appreciated for their good nutty taste. They are also very interesting from a nutritional point of view and are among the lowest calorie nuts. Let’s see how to grow a Pistachio tree, a tree which – whatever the species – is more suitable for the most southern regions.
Plant a pistachio tree
Before buying a Pistachio tree, it is interesting to know the main species and some of their specificities.
Some are at deciduous foliage. Others have a evergreen as is the case with Lentisk pistachio tree (Pistacia lentiscus). Also called Mastic Tree, it produces fruits that turn from red to black, edible but less tasty than pistachios from “true” pistachio tree (pistachio vera) whose foliage is deciduous.
The pistachio terebinth (Pistachio turpentine) also has deciduous foliage that turns flamboyant red in autumn, and it produces drupes relatively sour edible, used mainly for the development of a condiment oil. Note that we get from its bark an oleoresin which is none other than turpentine.
Once well rooted, the species pistachio vera for example supports rather chilly temperatures, around -15°C, and the Chinese pistachio (Pistacia chinensis), whose foliage is all red in autumn, has the reputation of being the most rustic of all since it tolerates down to -20°C. Its very aromatic deciduous foliage of a flamboyant red from October is extremely decorative, and its drupes turning from red to blue are a real delicacy for birds.
In any case, let us remember that the gender pistachio has a dozen species and that there are also cultivars.
The best time of year to plant a pistachio tree is located between september and november. This way, it has plenty of time to take root well before spring arrives. It is advisable to opt for a subject with bare roots rather than for a plant in a container. Here’s how.
- A month in advance, dig a large enough planting hole,
- Prepare the soil well, which involves removing weeds and plant debris, working it to loosen it and then mixing it with good manure,
- On D-Day, shorten the roots of the young Pistachio tree by 3 cm in order to refresh them,
- Soak the plant beforehand in a praline (mixture of manure and good soil) for a good two hours,
- Then install the shrub in the center of the hole, making sure that its roots are not bent,
- Place a tutor,
- Plug the hole,
- Tamp down,
- Water abundantly.
It is recommended to create a watering basin at the foot of the pistachio trees as soon as they are planted.
Growing a Pistachio Tree
Above all, it is necessary beware of biting frosts who are rampant in spring because they cause damage to flowering in all pistachio trees, whether they are a little chilly or not at all. If you live in a geographical area known for its very harsh winters, cultivation can be more difficult. It is a tree which supports the cold once it is adult and, small useful precision, which is not cultivated beyond 500 meters of altitude.
A pistachio tree needs soleilof heat and a beautiful brightness. It is therefore much more suited to the South of France, where it is then very easy to grow, than to the North of the Loire or, even worse, to our mountainous regions. As for the Pistachio tree’s preferred soil, it is ideally moderately calcareous, sec et perfectly drained. This tree therefore has its place in a Mediterranean garden.
Maintaining the Pistachio
As long as it benefits from a suitable environment, the Pistachio tree does not pose any particular difficulty.
Very resistant to drought, the Pistachio tree nevertheless needs regular watering throughout its growth during the summer, which also favors the production of pistachios. The rest of the year, it is content with less frequent watering.
The pistachio trees don’t like to be pruned. These are trees that heal very badly. Their pruning must therefore be limited to the elimination of dead wood, diseased or too frail branches. It allows at the same time to maintain a sufficiently dense branching. We therefore only carry out, if necessary, a very light size who should intervene between the beginning of January and at the latest the end of February.
If the branches are badly oriented, we of course take advantage of the opportunity to get back into shape, knowing that we must not intervene when pruning more than 12 or 13% of the crown of a Pistachio tree.
Pests and diseases
Not very sensitive to parasites and resistant to diseases, the Pistachio tree hardly poses a problem to the gardener. At most it can sometimes be touched by red spiders or even aphids. Note that pistachio terebinth is more sensitive to galle caused by certain species of aphids (Baizongia pistaciae, Ford formicaria et Forda marginata). This disease causes leaf mutation. These turn into a kind of large receptacle about twenty centimeters long in which the parasite lays its eggs. It is then necessary to remove all affected parts and burn them.
Whichever pistachio you want to plant, this tree produces very pretty fruits, grouped in clusters, and which take on beautiful colors throughout the ripening process, which increases the decorative advantage of this ornamental tree.
But make no mistake about it, a Pistachio tree grown alone will not produce fruit since it is a dioecious tree, i.e. unisex. It is therefore either male or female. It is absolutely essential to raise one male foot and two or three female feet to make fruiting possible. When buying plants from a nursery, do not hesitate to get good information from an advisor.
The pistachios arrive at maturity between September and November. Once harvested, they must benefit from a period of drying a week before being consumed. But you have to be patient before tasting the pistachios from the garden because, on average, a Pistachio tree only produces from 5 years of age.