By Mojtaba Zaifnejad, PhD
When applied fertilizers benefit soil health and plant growth, and are readily available to them, it is said that they are bioavailable. The extent of bioavailability of nutrients and fertilizers applied to soil and plants determines their effectiveness in improving soil health and crop yield.
In addition to the 4Rs approach, the factors affecting this mineral nutrient bioavailability include, but are not limited to, parent material of the fertilizers; their oxidation (saddening) or reduction (making happy) state for plants; what kind of carrier they ride on (chelated or complexed); whether they are taking healthy treats (right source of carbons) to the host, its children, and workers (beneficial microbes); and whether that treat is a long-lasting one for everybody. If the coming guest (fertilizer) can help the hosts (plant and soil) to handle bad neighbors (insects, disease, weeds, etc.) and harsh circumstances (droughts, floods, wind, etc.), that is better yet.
By the way, the 4Rs approach refers to Right source, Right rate, Right place, and Right time. Remember, we are going a few steps further—which includes the Right carrier (a big slow bus vs. a Ferrari) which we call Micro Carbon Technology® (MCT), that include lots of good treats (humic substances and organic acids vs. some salts only).
Humic substances (humic acids, fulvic acids, humates, etc.) are helpful in stabilizing the soil chemical environment for plants. They help plants directly and indirectly. Some humic substances do their good deed when there is a lot of hydrogen around, under acidic conditions (pH 1–4). Other humic substances do a good job where there is a hydrogen-oxygen (OH) around, where the pH is above 9. Having these two different kinds of humic substances in the mix will cover the bases.
Some agricultural soils have very few good microbes because they have been fed salts only, and lots of it. Don’t take me wrong, we all—including soils and plants—could use some salts. Having very few good microbes has created room for lots of bad microbes in some of the ag soil. This causes crops that are growing in those soils to have disease and be weak. Weak plants cannot resist attacks by bad guys in the soil and air (pathogenic microorganisms) and insects such as aphids, white flies, etc. Adding carbon and organic acids to a growing medium will help to increase the number of good guys in soils and plants.
A side note: Giving the wrong type of sugar to a growing medium might invite the bad guys, so do your homework.