A humate whose majority fraction is hydrophobic fulvic acid.
HUMISUN PLUS is declared as 85% total humic substances, of which 60–65% is hydrophobic fulvic acid and 20–25% is humic acid — fractions determined to ISO 19822:2018.
The scientific literature cited on this page concerns fulvic acid in general. Published results are not represented as trials of HUMISUN PLUS. Product-specific performance is the subject of the proposed greenhouse programme.
One number, properly defined.
The dossier corrects a common source of confusion: the fulvic and humic fractions sit inside the declared 85% total humic-substance content. They are not additional ingredients.
| Declared item | Value |
|---|---|
| Potassium humate | 90% |
| Total humic substances | 85% |
| of which hydrophobic fulvic acid | 60–65% |
| of which humic acid | 20–25% |
| Potassium (K₂O), water soluble | 12% |
| pH, 1% solution | 9–11 |
85% total humic substances
60–65 + 20–25 = 85. The fractions are the whole, not an addition.
Why the fulvic fraction is the mobile fraction.
The dossier distinguishes humic acid from hydrophobic fulvic acid by molecular mobility, solubility and functional chemistry. The proposed biological relevance is therefore framed around transport, signalling, oxidative protection and photosynthetic performance.
Membrane & uptake
Proposed increase in plasma-membrane permeability and H⁺-ATPase activity, supporting nutrient co-transport.
Measure: H⁺-ATPase · ion flux · tissue ICP
Hormonal signalling
Low-molecular-weight fractions are proposed to interact with auxin-, gibberellin- and cytokinin-responsive pathways, with ABA re-balancing under stress.
Measure: IAA · GA₃ · zeatin · ABA · JA · SA
Oxidative protection
The dossier proposes ROS scavenging and antioxidant-system induction, reducing oxidative damage under drought and salinity.
Measure: H₂O₂ · O₂⁻ · MDA · SOD · POD · CAT · APX
Photosynthetic capacity
Proposed protection of chloroplast function, chlorophyll and Calvin-cycle activity, with downstream effects on assimilation and water-use efficiency.
Measure: Pn · Gs · Tr · Fv/Fm · ΦPSII · Rubisco
What the literature reports under severe drought.
A 2025 greenhouse study on ‘Provence’ tomato applied fulvic acid at 400 mg·L⁻¹ under 30–35% field capacity. The dossier reports improvements across root architecture, photosynthesis, antioxidant status, water-use efficiency, yield and fruit quality.
Published fulvic-acid research ≠ product trial
These figures are from Song et al. (2025), Agronomy 15:1528, and refer to fulvic acid in general. They are included as scientific context, not as efficacy results for HUMISUN PLUS.
The dossier also cites research across tomato, chilli pepper, cucumber, tea, citrus, tree peony, oat, rice, lettuce/cucumber and apple rootstock.
Source named in the dossier: Song H., Zhu W., Guo Z. et al. (2025), “The Impact of Fulvic Acid on the Growth Physiology, Yield, and Quality of Tomatoes Under Drought Conditions”, Agronomy 15(7):1528.
Turn the hypothesis into product-specific evidence.
The dossier proposes a controlled tomato and sweet-pepper trial designed to test drought and salinity responses, dose response, root architecture, photosynthesis, hormones, yield, fruit quality and nutrient status.
Roots + oxidative status
WinRHIZO root architecture, H₂O₂, O₂⁻, MDA, proline, soluble sugars and antioxidant enzymes.
Gas exchange + fluorescence
Pn, Gs, Tr, Ci, WUE, Fv/Fm, ΦPSII, pigments and Calvin-cycle enzymes.
Hormones + gene expression
IAA, GA₃/GA₄, zeatin, ABA, JA, SA and ACC, with qRT-PCR for selected response pathways.
Yield + fruit quality
Fruit number, weight, set, marketable yield, lycopene/capsaicinoids, vitamin C, soluble solids and shelf life.
Nutrients + ion balance
N, P, K, Ca, Mg and micronutrients by ICP-OES; Na⁺ and K⁺/Na⁺ ratio in the salinity arm.
Effect size + dose response
Two-way ANOVA, dose-response modelling, PCA, correlations and confidence intervals — not p-values alone.
Designed for technical buyers, growers and registration teams.
The commercial strength of HUMISUN PLUS is not a large number without context. It is a defined fraction, a named analytical method, a consistent specification and a proposed evidence programme that can connect chemistry to plant physiology.
Documentation discipline
The dossier recommends keeping the declaration, certificate of analysis, technical data sheet and safety data sheet aligned on the same figure and method.
For technical files, the dossier identifies ISO 19822:2018 as the fractionation reference and notes consistency with IHSS separation principles and ISO 12782-4/-5.
Build the evidence around the fraction.
Contact Zenith Growth Tech GmbH for the product dossier, technical documentation and discussion of the proposed greenhouse programme.
Industriestr. 1 · 31180 Giesen, OT Emmerke · Germany