growing hot climate plants in cool climates and cool climate plants in hot climates

Having grown up in a hot state in the southeastern US, but on top of a mile high mountain, in a rainforest.... and wanting to grow the low country vegetables I came to love on my maternal grandparents' farm, I have a lot of experience growing zone 7-8 plants in zone 5.  I grew up with greenhouses, cloches and row covers.  Lack of sun was really my biggest challenge.  Sun traps an hugelkultur beds were an absolute revelation for me.  I think back now at the possibility of growing citrus at high elevation, like Sepp Holzer and could kick myself for not discovering his techniques earlier!  

Now, I live in zone 7b/8 and find growing cooler climate crops more of an issue.  I'm trying to utilize shade, north facing slopes, stones, and water.... but I still can't grow ramps and mountain herbs.  Can anyone offer advice on that?  I walked past some weeping willows the other day and was reminded of their natural air conditioning effect.... is there a way I could utilize this on a property with no flowing water?  Is there a way to increase cooling breezes using trees and shrubs?  Any other ideas?

You don't need flowing water to grow good weeping willow trees, you just have to keep the soil wet enough for them.
Thick layers of mulch under a willow goes a long way at keeping the moisture in the soil for them.
I like to use wood chips for this since as they decay they feed the soil organisms which then feed the tree, as I replenish the wood chips I keep the circle going.

Locating the natural breezes on your land is another key to being able to grow cooler weather plants in the south.
Add shading trees to this area and you can get quite a temperature drop. (I have two places where it will be 20 degrees cooler in the hottest part of the day)

Steep hugels are great for creating microclimates and you can make use of these for lots of cooler weather items like lettuces, radishes, beets, carrots, kale, mints, and many others that like it a bit cooler than our hot southern summers.

Bryant RedHawk wrote:You don't need flowing water to grow good weeping willow trees, you just have to keep the soil wet enough for them.
Thick layers of mulch under a willow goes a long way at keeping the moisture in the soil for them.
I like to use wood chips for this since as they decay they feed the soil organisms which then feed the tree, as I replenish the wood chips I keep the circle going.

Locating the natural breezes on your land is another key to being able to grow cooler weather plants in the south.
Add shading trees to this area and you can get quite a temperature drop. (I have two places where it will be 20 degrees cooler in the hottest part of the day)

Steep hugels are great for creating microclimates and you can make use of these for lots of cooler weather items like lettuces, radishes, beets, carrots, kale, mints, and many others that like it a bit cooler than our hot southern summers.

That is good advice - thanks!