Pistachios grow on small deciduous trees (Pistacia vera) that reach about 6 meters tall. These trees are dioecious, meaning male and female flowers grow on separate trees, so both male and female trees are needed for successful nut production
. Growing conditions:
- Pistachio trees thrive in regions with hot, dry summers (temperatures often above 30°C/86°F) and cold winters that provide a chill period (temperatures below 7°C/45°F for about 6 weeks)
- They prefer arid, semi-desert climates with low humidity and well-drained, sandy or loamy soil
- The trees are drought-tolerant once established but require regular deep watering during the growing season for good nut production
Planting and care:
- Plant pistachio trees in early spring while dormant, spacing them about 20 to 30 feet apart to allow room for growth and airflow
- The planting hole should be deep and wide enough to accommodate the root system, with the root ball placed at soil level
- Mulch around the base helps retain moisture and suppress weeds
- Prune in winter to remove dead or damaged wood and maintain a clear trunk for about 1 meter before allowing a spreading crown to develop
Pollination and fruiting:
- Male trees produce pollen that is carried by wind to female trees for pollination, so planting one male tree for every 8 to 15 female trees is recommended
- Trees take about 5 to 8 years to begin producing nuts, reaching full production around 15 to 20 years
- Pistachio trees are alternate-bearing, producing heavy crops one year and lighter crops the next
Harvesting:
- Nuts are harvested when their hulls start to split open naturally
- Mechanical shaking is often used in commercial orchards to collect the nuts
In summary, pistachios grow on dioecious trees that require hot summers, cold winters, well-drained soil, and both male and female trees for pollination. They take several years to mature and produce nuts, which are harvested when the hulls split open
