Pistachio trees are native to desert regions where it is very sunny, hot and dry. But it can also get very cold there at night, so older trees can survive sub-zero temperatures well for a short time.
Are pistachio trees hardy?
Pistachio trees are conditionally hardy and can tolerate temperatures down to -10 °C. For optimal winter protection outdoors, the roots should be covered with foil or jute bags and the branches should be wrapped with straw. Container plants ideally overwinter at around 10 °C in frost-free rooms.
Protecting pistachio trees outdoors from the cold
Pistachio trees should only be planted outdoors in locations where it is very sunny and warm. The soil should be well dry. If the moisture is too high, the roots will rot.
The temperatures in winter must not fall below minus ten degrees. Then the branches and roots freeze.
To be on the safe side, an outdoor pistachio tree should be protected from the cold in winter.
Winter protection for the pistachio tree
Cover the soil with foil or jute bags to protect the soil from heat loss. Mulch covers are not so suitable because they supply the soil with too many nutrients.
Protect the branches with straw (€22.00 on Amazon) or other suitable materials. But make sure that the tree continues to get enough air.
You don't have to water the pistachio tree in winter. The tree needs almost no moisture during the rest period.
Overwintering potted plants
If you grow your pistachio trees in a pot, you should place them outdoors in summer. This is the only way the flowers can be fertilized by the wind.
In winter, place the pots in a frost-free place. Temperatures around ten degrees are sufficient. Since the tree loses its leaves during the dormant period, it does not need as much light as in summer.
Bring the pistachio trees into the house when the temperatures outside are approaching freezing point.
Suitable wintering options for pistachio trees
- Frost-free basement entrance
- dry basement room or
- Attic with small window
- Hallway window
- Non-heated winter garden
- North window sill
Care during wintering
Let the soil in the pot almost dry out over the winter and only water very little if the potting soil appears completely dry.
Check the tree from time to time for pest infestation.
Tips & Tricks
Due to the cold temperatures in Germany, it is best to plant your pistachio trees grown from pistachio seeds in a pot. The trees in the house can overwinter well at low temperatures.