Where do cork oak trees grow?
Cork oaks grow in forests alongside other oaks, wild olive trees, stone, and maritime pines. The forests in which they grow are incredibly diverse. In fact, they are some of the most diverse forests for both animal and plant life. Typically, they are found in southwestern Europe, as well as northwestern Africa. Annual production is about 200,000 tons. (source):
1. Portugal (49%)
2. Spain (6%)
3. Marocco (5%)
4. Algeria (4%)
5. Tunisia (3%)
6. Italy (3%)
The cork oak favors acidic soil and needs a hot, dry summer season combined with a cold and moist winter. They can generally be found in open woodlands, on hills and lower slopes.
In those areas, the cork oak faces the same threats that other trees face: deforestation, fire, climate change, disease, and agricultural expansion.
Portugal’s cork processing is a highly developed industry, and this has given rise to a unique mixed farming landscape including the cork oak tree. This unique mixed farming system is not agriculture, forestry nor pastoralism, but instead, an integrated mix of all three that ensures that greatest abundance of conditions that are often harsh and inhospitable.
Interestingly, they also have a law which prevents anyone from cutting down a cork oak tree, whether that tree is dead or alive.
Since the Middle Ages, Spain and Portugal have grown cork oaks in open woodlands grazed by sheep and cattle. They do not use fertilizers, herbicides or irrigation, and because of this, rare and endangered wildlife thrives in the area.
Can they grow anywhere else?
Because the cork oak is a hearty, evergreen shade tree, many American gardeners wish to use them. The cork oak can be planted in the United States, with the most important planting limitation being frost.
They can be planted on the coasts since they’re impervious to salt spray, and their water requirements are anything from dry to moderate. Cork oak trees are quite common in the western U.S., particularly the UC Davis campus and Disneyland grounds.
How do you grow a cork oak tree?
If you want to grow a cork oak tree on your own property, the first thing you’ll want to do is select good cork oak acorns.
Plant the acorns in sandy, mildly acidic soil and make sure they get full sun. Plant them in a triangle, approximately 3 inches deep and a foot apart.
Cover with hardware cloth to prevent disturbance, and check them in the spring for germination.
Once they germinate, keep the strongest seedling, and transplant the others. Fertilize the ground around the seedling, and give it a thorough watering once a month. Mature cork oak trees do not require watering.
While there is a traditional answer to the question of where do cork oak trees grow, they can be grown in other places. With the right conditions and patience, the potential to have a 70-foot cork oak tree in your backyard someday does exist.