The plants and the biology of the soil have formed symbiotic relationships exchanging plant sugars for essential nutrients through vast underground networks (providing the soil is in its natural state). This is a vital understanding, as plants need many trace elements and nutrients that may not be present in the soil where they are growing . The plants source what they need in these situations via the beneficial microbial, yeast and fungi connections, which in turn increases the health of the plants. Having biologically active soil ensures that the plants can source any nutrient that they require for their growth and health from the biology present in the soil, and they can also communicate with each other over vast distances, thus warning of potential challenges coming, enabling plants to make biochemical changes to adapt to the challenge and create resistance within the plant, thus making them healthier. This health is then passed on to us.
It is also well understood that inoculating plants increases their health, and protects them against viral, bacterial and fungal pathogens and diseases. This happens as a result of the inoculation (much the same way as probiotics work) - the beneficial microbes will directly compete with the pathogens - and in some cases will produce antibiotics at the site of the infection - it is in the benefical microbes, yeasts and fungi's interest to assist and protect the plant, as they are relying on the sugars created by photosynthesis by their host for their survival. Hence a beneficial symbiosis. These beneficial micro-organisms rely on certain conditions to thrive - they need the plants, they need undisturbed soil (shallow infrequent tilling will have a minimal impact, especially if the soil is not inverted during the tilling - we love our power harrow for this), they need organic practises as many commercial conventional farms spray fungicides, and a host of other chemicals which deeply disturb the soil ecology.
In the situation of the hydroponically grown plants, they can be housed in warehouses and grown under artificial light, or in large greenhouses creating the most perfect conditions for their growth. So, what's wrong with that I hear you say...?
Well in the field there are many potential challenges to a small seed as it grows to be a seedling and then a mature plant. It will experience extreme climatic events, pests, sunlight, pathogens, insects, weeds, animals, butterflies, birds, bees, humans, children - and all of life... When a plant is under attack from a pathogen or other threat, the plant will have an immune response creating different phytochemistry (not exactly the same way that we do, however protective chemicals are sourced from the active biology present in the soil, and generated from within the plant, as well as the benficial microbes which consume the pathogen or produce antibiotics at the site of the infection). When the plant overcomes the challenge, it has increased its resilience, health and nutrient density in its chemistry, which is passed on when consumed, increasing our health in kind. Thus the soil-grown plant has access to all 90+ elements, trace element and nutrients and medicines that may be required for its health, and indeed for ours.
The hydroponic plants are not challenged. They live in a chemical soup of what is currently believed to be the only nutrients required for the plants growth (often in the range of 6-17 chemically synthesized nutrients). Plants have 2 types of roots - one for absorbing water, and one for absorbing nutrients. The roots sit in the liquid, thus they are unable to choose to uptake from the roots- a bit like force feeding them, so they fill up with fluid.
We have all eaten commercial conventional hydroponic produce, often it just doesn't taste of much, even though it looks exactly like the soil-grown produce - in fact often more perfect. This lack of flavour is due to the lack of nutrient density that these plants have, and their disconnection from the soil food web. This is also the reason why the produce does not last long post - harvest, and why it is then treated with a preservative before sale, further diminishing its value as food.
We ensure our soil is biologically active by using organic, minimal till practises and by applying inoculations of compost tea regularly (feature piccy of our brewer in action). I continue to be fascinated by these connections, and by learning more about increasing the biology of the soil, so it becomes more biologically active and grows more living, alive, food.