Soil preparation for greenhouse grow. Help!

Not sure how to create a good soil life for the 50 gallon pots. It’s a kush strain if that helps and they are only veged to 2 feet and put into a light deprivation greenhouse in oregon for 12/12 Starting in december. I would like general info and steps if anybody can recommend it. Also organic is what I’m looking for but I’m trying to pull a descent yeild per plant.thanks

I would recommend starting with ProMix BX. All the amendments you need. No soil included. You can add soil and manure, or compost or guano, or worm castings. to romix to build the perfect grow media.