altitude

Greetings from Oregon. I am an old longtime criminal made legal by the enlightened voters in my home State. Planning on trying an outdoor grow this spring. I live in the High Desert, (Yes it is really called that) at 3600ft. Just wondering if any out there have experience growing at altitude...

Say I have a Sativa 'Zeus' and I can grow it outdoors in grow zone 7b but at about 1200 m, does altitude take away from the grow zone? I mean the heat that I need for the Sativa? Or should I stay closer to home in zone 6a at a lesser altitude? Did anyone understand that?