The more crops we grow in our soil with conventional methods, the more we mine all the nutrition out of the soil and feed our children empty calories (think donuts from the garden!). We can do better, and nutrient dense agriculture is a great method to quickly re-mineralized the soil that the glaciers scraped clean over 10,000 years ago.
Yes, getting a soil test and measuring exact quantities in soil is great. Don’t get overwhelmed, buy a bag of the spring and fall blend and spread the minerals over your soil. Add in some organic matter, and you will be amazed how you soil biology and food grown will become much healthier. At our school we re-mineralized, and mulched with paper and wood chips on top and people are amazed at the produce we grew in the first year on marginal soil!
Bio nutrient food association: http://bionutrient.org/
An additional step you can take is to mulch or compost with seaweed, since there are dozens of minerals in the sea that get transferred to your garden. This is how the Findhorn community in northern Scotland were growing enormous 50 pound cabbages in the sandy soil up there!
Findhorn Ecovillage: http://www.ecovillagefindhorn.com/