Pistachio tree (Pistacia vera) KERMAN

The most widely cultivated variety of pistachio prized for its hardiness and productivity. This selection is appreciated for its large, round and tasty fruits with green seeds, which are commonly consumed fresh or roasted. It prefers sandy-loamy, limestone soils that are deep and well-drained. The pistachio tree thrives particularly well in a continental Mediterranean climate with long, dry, and hot summers and dry, quite cold winters. Pistachios, like walnuts and almonds, are oilseeds or nuts. They are rich in lipids, complex carbohydrates, proteins, vitamins B, K, and E. They also contain manganese, phosphorus, and magnesium.

Origin: female variety of pistachio tree originating from Iran
Rootstocks: UCB1 (Pistacia atlantica x Pistacia integerrima), obtained by sowing seeds, hardy hybrid developed at the University of California Berkeley. Although less tolerant than other rootstocks to drought, cold, and salinity stress, it is valued as a pistachio rootstock because of its resistance to Verticillium dahliae. This hybrid Pistacia species is considered to be the most reliable source of resistance to soil pathogens to date.
Vigour: its growth is slow, but it can live for several centuries. The pistachio tree can reach a height of 4 to 6 m with a spread of 3 to 5 m. Female pistachio trees have a slightly weeping habit, while male trees are upright. Its foliage is deciduous. Overall, it appreciates the same growing conditions as other Mediterranean fruit trees.
Blossom: it is a dioecious tree, meaning that there are female plants and male plants. The cymose inflorescences bloom abundantly in mid-April. Female inflorescences are large, slightly loose and trailing, while the inflorescences of male trees are dense. The Kerman Pistachio tree only bears female flowers. They need to be pollinated by a male tree to bear fruit, particularly the Pistacia vera Peters. Requires a sufficiently long period of cold to induce flowering. The abundant pollen is carried by the wind. To ensure satisfactory pollination, it is essential to determine the direction of the prevailing wind when planting pistachio trees. One male plant will pollinate 4 to 7 female plants.
Fruits: the tree produces large clusters of round, large fruits with a diameter of 2 cm. The fleshy, resinous-smelling husk turns bright red when fully ripe. Beneath this aromatic and highly coloured husk lies a large, green, nutritious, and tasty seed, whose edible kernel is protected by a whitish shell that hardens and opens up when ripe.
Taste: sweet
Harvest season: the fruits ripen between late August and September. The tree produces its first harvest at the age of 5 to 6 years.
Yield: high productivity. This variety is less prone to alternate bearing.
Disease resistance: reliably resists attack by pests and fungal diseases, no chemical protection is required during vegetation
Frost resistance: the mature tree is hardy to -15°C (USDA zone 7b). Young plants must be protected from frost during the first two winters.
Planting and care: the tree should always be planted in a sunny, well-ventilated, and airy location. It requires deep, well-drained, sandy-loamy, slightly alkaline soil. To ensure a good start, it is important to plant it in deeply worked soil to allow its roots to descend more quickly, and to water it deeply but infrequently from planting until the first two summers. Young plants need support to establish firmly roots. The female pistachio tree is wind-pollinated. It is imperative to plant the pollinator, the male tree, facing the prevailing wind so that its pollen is carried to the inflorescences of the female tree. It is also necessary to choose a compatible pollinator that will flower with the female plants. Adding potassium and magnesium can be beneficial, as well as applying organic fertiliser in late winter. Pruning of the fruit-bearing pistachio tree is not obligatory, as it does not like it much and heals poorly. However, a light pruning can be done in January-February. Dead wood is removed at the end of winter.

The wild Pistacia vera is native to Central Asia, particularly Iran and Turkestan. In these mountainous, harsh, arid regions, which are very hot in summer and cold and dry in winter, it survives in the form of sparse and residual forests called wooded steppes. The cultivation of the pistachio tree dates back approximately 4000 years. It originated in the northern part of present-day Iraq and then spread to all Mediterranean regions under the influence of the Romans. This tree, emblematic of Mediterranean civilization, along with the almond tree, the olive tree, and the pomegranate tree, is once again being considered. Its low water requirements, as well as its high added value, attract the attention of agronomists and farmers who see it as a tree of the future in the face of climate change. The true Pistachio tree belongs to the Anacardiaceae family, just like the mango tree, and the cashew tree.