Outdoor Auto Soil Mix-same or different ?

[JaPinkman]

I'm germinating right now and am planning on going outdoors with my first auto. My question is this: In the past I've grown photo-period plants in soil using a mix of about 50% what I had in the ground with 50% Ocean Forest. My soil must be decent as the results have been pretty good. Now I'm planning on a mix of about 40% soil and the rest perlite and coco, in bags to keep the size down a little. It makes for a much nicer, aerated, loose soil but I've been told in this forum that it dries out super fast in the outdoors. Should I be using a mix that is mostly soil instead?
Thanks for any and all advice