Organic farming in the conventional sense of using natural methods like permaculture and integrated animal husbandry practices have shown that depleted soils can be coaxed back into life. The process is long and slow; for after all nurturing nature cannot be hastened.
Technology has answers; though not in its fullest sense. The primary result of soil analysis does give an accurate picture of the mineral content of the soil. The essential nutrients that these minerals are supposed to give for the plants are also calculated. What is lacking is the delivery mechanism.
In its natural state fertile soil is blessed with micro-organisms; these micro-organisms help the plants to assimilate the minerals (which the micro-organisms convert from dead organic matter) and various nutrients. The accuracy of the nutrients that the plant assimilates is a complex reaction of photosynthesis (the conversion of sunlight or light energy to a chemical energy) that fuels all of the plant's activities. This complexity is the source for essential nutrients for the various parts of the plant. For example polysaccharides (type of carbohydrates like cellulose) are circulated throughout the plant while at the same time a portion of it flows back into the soil through the root system (like a two way highway) for production of fulvic acids. This being complex is also life threatening as this circuitous route is akin to an electric circuit. Any imbalance in the system can cause adverse reactions leading to fatal consequences for the plant.
So two things become very clear for healthy plant growth; accurate nutrition in the quantities specified and essential nutrients delivered at the proper time. A few organizations devoted to organic farming supplements have been quite successful in creating a water soluble mix that contains the desired nutrients both qualitatively and quantitatively. Being water soluble enables the root system of the plant for the correct uptake.