Need help making a good soil mix

Next year I want to grow only a few plants. So I'm planning on making them amazing. As always. I want to know what kind of soil I should use. It's going to be outside in the ground so I need something for the plants whole life cycle. Here is my plan. I an thinking of using FFOF and light warrior mixed with compost and perlite along with the natural soil outside. I am going to dig at least a 2x2 hole for each plant and place gravel in the bottom for good drainage. They are going to get about 7-8 hours of light going into fall for flowering. It is also going to be an indica strain because it gets pretty cold up here in October. I haven't ever ph'd my soil or water. Should I even though is going to be outside. Will that combo be to strong and burn them. Also what kind of liquid ferts should I use?