Plants absorb iron in the ferrous (bivalent iron) form from the roots. Even as the earth is said to be a planet of iron, there is a lot of iron in the soil, however most of that is ferric (trivalent iron) that plants are unable to absorb in that form. Plants use their energy to turn trivalent iron into bivalent iron before absorbing it from their roots.
Our TetsuRiki Agri/TetsuRiki Aqua products are based on an understanding of the mechanisms at work within plants so that iron can be absorbed even if the plant is weak, such as in poor soil or weather, lead to cultivating healthy plants.