As a late comer to this poll, am I allowed to suggest our own soil, Thrive Living Soil from www.thrivecentre.co.za ? We tend to find that a lot of soil producers try to throw the kitchen sink into a soil, without really understanding what elements do what. The whole "bullshit baffles brains" approach. So, for instance rock dust can stall your plants if you haven't also included indigenous microbes collected during the winter months. That is because indigenous soil microbes move deeper down in the soil layers during winter, in order to decompose the tougher mineral matter, versus more usual organic matter in summer months.
Some of the key components to get right are obviously your base NPK ratio. We aim for around 6:3:2 with a strong and sustained Nitrogen boost for initial growth, and then a slower and more sustained release of Phosphorous and Potassium for fruiting and flowering. Getting the timing right is important and that's where the inoculated biochar comes into play. It's also important that the composting process introduces living, microbial matter into the soil food web, and that it finds a home in the biochar, establishing a symbiotic relationship with the plant roots. A good living soil should give you at least 2 full strong growths without refeeding with compost and/or organic fertilisers. Although you really want to be feeding and fertilising your soil, and not the plant i.e. the plant needs to talk to the soil for what it needs, and not let the human try and force feed the plant.
We are exceptionally lucky in that our soils have excellent natural mycelium and perfect pH for cannabis, developed over thousands of years in Hogsback. That is something that no soil producer can ever reproduce on their own. We also produce most of our own amendments, such as our oak and bamboo biochar (Japanese style) which also gives us superb wood vinegar. This is not that well known in South Africa but wood vinegar is probably your number one all-round Natural insecticide and fungicide. As far as I know we are the only ones producing it in SA, as not that many have sustainable oak and bamboo resources. It is Nature's own plant immune booster, root growth stimulant and flavour enhancer. You can read more about it at www.woodvinegar.org