Ammonium lignosulfonate is a lignosulfonate in which ammonium is the main counter-ion. In agriculture it is evaluated as a fertilizer-granulation binder, a component of liquid nutrient formulations and, in published research, as a soil amendment against soil-borne potato diseases. The ammonium counter-ion gives the material a measurable nitrogen content. By itself, that does not establish fertilizer value, nitrogen availability, crop safety or field efficacy. This page sets out what the current grade documents state, what the soil research actually reports and how to design a trial that answers a real question.
For potassium grades see potassium lignosulfonate in agriculture; for all salt forms see the lignosulfonates in agriculture guide.
Current grade data: powder and liquid
Values from Green Agrochem’s current technical data sheets for Ammonium Lignosulfonate, Agri/Fertilizer Grade (GAC-NHLS-Agri, Rev. 1.0) and Ammonium Lignosulfonate, Fertilizer Grade (Liquid) (GAC-NHLS-FERT, Rev. 2.0). Both documents describe these as typical production results; the COA issued with each shipment reports batch values.
| Parameter | GAC-NHLS-Agri (powder) | GAC-NHLS-FERT (liquid) |
|---|---|---|
| Appearance | Yellow-brown powder | Black/brown liquid |
| pH | 4–7 | 4.0–7.0 |
| Dry matter / solids | Dry matter 95% min | Solids 50% min |
| Total nitrogen (N) | 3–5% | 3–5% |
| Lignosulphonate content | 50% min | 50% min |
| Sulphate | 5% min | 5% min |
| Calcium & magnesium | 2% min | Not stated |
| Water-insoluble matter | 1.0% max | Not stated |
| Total reducing matter | 7% | Not stated |
| Density | 0.532 g/cm³ | Not stated |
| Moisture | 5% max | Balance to solids (50% max) |
| Packaging / shelf life | 25 kg bags or 500–600 kg FIBC | Flexitank or IBC; 12 months |
For a liquid, moisture is the balance to the solids content; for the powder, dry matter and moisture together account for the whole sample. Older web content quoted 6–8% nitrogen for ammonium lignosulfonate; that figure does not apply to either current grade. Before a nitrogen figure is used in a nutrient declaration, confirm total versus ammoniacal nitrogen, method, basis (as-supplied or dry), tolerance and the labelling rules of the destination market.
What the ammonium counter-ion changes
| Aspect | Technical point | What to check |
|---|---|---|
| Nitrogen contribution | Ammonium nitrogen is associated with the lignosulfonate matrix; at 3–5% N it is a minor nitrogen source compared with urea or ammonium salts. | Calculate delivered N on the same basis as the rest of the formula. |
| pH sensitivity | Under alkaline conditions ammonium can convert to ammonia and be lost from the formulation or the soil surface. | Formulation pH, alkaline ingredients, drying temperature, odour during processing. |
| Sulphate and salt load | Sulphate is 5% min in both grades and adds to total salt input. | Salt index and cumulative loading in sensitive crops or poorly drained soils. |
| What it does not prove | The counter-ion does not demonstrate controlled release, nitrogen-use efficiency, growth stimulation or yield response. | Each requires its own controlled evidence. |
Formulation roles to evaluate
Fertilizer granulation and binding
Ammonium lignosulfonate may be screened as a binder or processing aid in compound-fertilizer granulation. Results depend on raw materials, moisture, recycle ratio, equipment and drying profile. Compare candidate binders on an equal dry-lignosulfonate basis and measure granule formation, crushing strength, attrition, caking and redissolution.
Liquid nutrient and micronutrient formulations
The liquid grade may help disperse solids or complex metal ions in some formulations. Check pH, ionic strength, water hardness, metal salts, precipitation, viscosity and storage stability in the complete formula. “Complexed” and “chelated” are not interchangeable regulatory terms; use the wording the required analysis supports in the target market.
Soil amendment research
Soil use requires diagnosis and controlled field evidence. Calculate delivered nitrogen, sulphate and total salt load from the exact-grade analysis. Nitrogen content alone does not define a field rate.
What the published soil research shows
Most performance figures quoted online for ammonium lignosulfonate trace back to potato-field research on soil-borne disease. The results are real but tied to the tested material, rate, soil and crop. They are published research results, not product specifications or recommended rates.
| Reported result | Material and system | Conditions and basis | Source | How to interpret it |
|---|---|---|---|---|
| Root-lesion nematode counts fell 32.68% between spring and fall samples, while the untreated control rose 92.11% | Ammonium lignosulfonate soil amendment, potato field plots, New Brunswick, Canada | 6 t/ha applied with water 14 days before planting; four replicates; 2017–2018 seasons combined | Al-Mughrabi, Poirier & Khabbaz (2025), Biology 14(5):514, doi:10.3390/biology14050514 | One regional field trial among several products. The registered nematicide in the same trial reduced counts by 66.67%. Not a pesticide claim. |
| Verticillium CFU per gram of soil fell 53.3% between spring and fall samples, while the control rose 344.4% | Same trial | Same conditions | Same source | In that trial the result was not statistically separated from several other products. Not a disease-control guarantee. |
| Field evaluation of potato scab and Verticillium wilt | Ammonium lignosulfonate soil amendment in four Ontario potato fields | See the original paper for rates and design | Soltani, Conn, Abbasi & Lazarovits (2002), Canadian Journal of Plant Pathology 24(3):332–339, doi:10.1080/07060660209507018 | Background research on the disease question; consult the paper before quoting any figure. |
Two practical points follow from the 2025 trial. First, 6 t/ha is a research rate for a soil-borne disease study, far above any formulation-additive level. With a 3–5% N grade it would also deliver roughly 180–300 kg N/ha (calculated from the TDS range, not reported by the study), which must be accounted for in the nutrient plan. Second, claims that a product controls pathogens, nematodes or disease can trigger pesticide or plant-protection registration; review them for each market before use.
Earlier versions of this content quoted incubation results (very large increases in soil bacteria and fungi, 60–95% nematode reductions at 0.5–1.0% soil mixtures, a 6–8 week disease delay). Those figures could not be traced to a verifiable source with full conditions and have been removed.
Designing a useful trial
| Question | What to measure | Minimum comparison |
|---|---|---|
| Does the grade improve formulation handling? | Solubility, precipitation, viscosity, storage stability, ammonia odour, nozzle or emitter behaviour | Same formula without lignosulfonate, and the incumbent additive |
| Does it affect nitrogen availability? | Mineral N in soil over time, tissue N, crop response | Equal-nitrogen control from a conventional source |
| Does it affect a soil-borne disease? | Pathogen or nematode counts at defined timings, disease incidence, yield | Untreated control and a registered standard |
| Does it affect emergence or yield? | Germination, emergence, biomass, marketable yield, crop safety | Randomized, replicated treatments with predefined statistics |
- Define one primary formulation or agronomic objective.
- Calculate dry lignosulfonate, nitrogen and sulphate delivery from verified analysis, stating the basis (as-supplied, dry matter or measured lignosulfonate).
- Include an untreated control and an equal-nitrogen or commercial benchmark.
- Test compatibility, storage and processing before crop work.
- Run replicated trials with predefined endpoints, and monitor phytotoxicity as well as the intended effect.
- Approve the exact grade and test basis before any commercial recommendation.
Neither ammonium TDS gives an application rate. Any starting rate must be developed for the specific formulation and stated as a recommended starting trial range with its calculation basis.
Documents to request
- TDS for the exact grade code, with revision.
- SDS for handling, storage and transport.
- COA with batch values, units and test methods, including total and ammoniacal nitrogen where nutrient declarations are planned.
- Market-specific regulatory evidence for any fertilizer, soil-amendment or organic-production claim.
- Change-control commitment for feedstock, process or specification changes.
Claims that should not be assumed
Do not describe ammonium lignosulfonate as a slow-release fertilizer, nitrogen-efficiency enhancer, growth stimulant, disease-control agent, soil-microbiome enhancer, non-toxic, biodegradable, organic-compliant or environmentally superior without product-specific evidence and a market-specific regulatory review.
Related resources
- Ammonium lignosulfonate product page
- Potassium lignosulfonate in agriculture
- Lignosulfonates in fertilizer formulation
- Liquid lignosulfonate formulation and handling
- Soil diagnosis and field-trial guide
Send the intended formulation, target nitrogen analysis, water quality, process, crop, destination market and test plan to info@greenagrochem.com for exact-grade documents and samples.