Whats the best way to plant trees in Mediterranean climates?

I have some land in Strawberry Valley CA, in the foothills of the northern sierra. Winters are extremely wet and rainy, with occasional heavy but quick melting snow. The problem is summers are bone dry, as most summer thunderstorms, while rare, only occur in the southern high sierra where convection is much stronger.


I have plans to plant a few non natives here(Fruit trees, Sugar Maple, Amur Maackia, and many others), which arent well adapted to the dry summers, but i know its possible. Is there any way to mound or trench the soil in a way to capture as much winter rainfall and store it so the plants can use it during the hot dry summers?

I live where we get very little rain all year so I can understand your struggles.

The Ellen White Method of tree planting might help your situation:



Here are some threads that folks might find interesting:

https://permies.com/t/160325/Ellen-White-Method-tree-planting

https://permies.com/t/135920/Ellen-White-tree-planting-method

Water is your friend.  If you can get the trees through the first two years by keeping them watered then there might be some success in your future.

Covercrop:
daikon radish everywhere, they will give you a 3ft tuber and a 6ft root system that will allow water to infiltrate into the soil.
dutch clover so that the plants can have some extra nitrogren to grow once it warms up.

Earthworks:
A swale at the top of your property sounds like a great idea.

Cultivar Selection:
Grow your plants from seed, you need that taproot that goes down 30ft+ so that it can survive the dry summer. Transplated trees don't have a root system that is as good, but feel free to graft a cultivar on top that is more to your liking. Personally I would just keep alot of the sour fruits and add honey to them, so yeah get 4 or so honeybee flow-hives.
If you see a wild plant growing zero/minimal irrigation get a seed or two from it, they are locally adapted.

Your climate chart shows that you get a lot of water and a lot of snow. Much, much more than typical 400-600 mm for Mediterranean climates. I got 380 mm this winter/spring.

1. Pick species that are drought resistant.
2. Improve your soil by adding organic matter. In my case it makes a difference between thriving and dying.
3. Mulch a lot.
4. Try to pick spots with some afternoon shade.

We intend to plant trees in the fall. That gives them the whole rainy season to put down roots before things turn hot. Then we irrigate them during the summers for the first two years.