Organic acids
Citric, phytic, gluconic, glutamic and phosphoric acid appear across almost every product. They do more work than their position on a label suggests.
What they do
Organic acids serve several functions simultaneously in a foliar or soil product, which is why they are nearly ubiquitous.
They adjust and buffer pH, which matters because spray water is often alkaline and many actives are pH-sensitive. They chelate metal cations, keeping micronutrients soluble and preventing precipitation in the tank — a weaker but more benign alternative to synthetic chelates. They improve cuticular penetration of foliar applications. And several are metabolic intermediates in their own right, entering the tricarboxylic acid cycle directly.
The acids in the range
Citric acid is the most widely used, appearing in most products. Tricarboxylic, a good chelator, a TCA cycle intermediate, and safe and inexpensive. Also, as noted on the beauty side, a common cosmetic pH adjuster.
Phytic acid (inositol hexakisphosphate) is the phosphorus storage compound of seeds and a very strong chelator of divalent cations. In Balance Boost, Calcium Boost and Color Boost. Its strong binding is double-edged: it holds micronutrients in solution but can also reduce their availability, which is why phytate is regarded as an antinutrient in animal feed.
Gluconic acid in Vita Boost — a mild chelator, produced by glucose oxidation. Note the outstanding data question on that product's two conflicting formulations.
Glutamic acid in Micro Boost — an amino acid functioning as a chelator and a nitrogen metabolism intermediate.
Phosphoric acid in Balance Boost and Phosphorus Pro — here principally a phosphorus source and strong acidifier rather than a chelator.
Why this matters practically
Two things. First, tank-mix compatibility is largely governed by pH, and organic acids are usually what is holding a mix stable — which is why adding an alkaline product such as potassium silicate to an acidified mix can cause precipitation. Second, the presence of a chelating organic acid can substitute in part for a synthetic chelate, which is the more natural route to the same end and worth stating.
What does organic acids not do?
They supply negligible nutrition at use rates. They do not replace strong synthetic chelates in high-pH soils. And low pH is not inherently good: excessively acidified sprays can damage foliage.