Liquid Seaweed and Kelp Fertiliser
Liquid Mineral Soil Amendment
- Naturally occurring minerals
- Made with microbial cultures
- No artificial additives or preservatives
- Made-to-order bulk supply—minimum 180 L
- DIY systems, ingredients, training
*Limited stock available. Made to order (allow 10–12 weeks for processing). Contact us for availability.
SONIC Liquid Seaweed
Biofertiliser
Pricing Guide
Choose your Supply Option
MADE-TO-ORDER PRODUCTS
We make your liquid fish and seaweed biofertiliser and deliver it to your farm.
Product Price Range:
$2.30-3.90/L
Includes: Finished liquid concentrate product, ready to dilute and apply.
Size Options: 180L (20L Drums) or 1,000L IBC per product
Freight: Quoted separately for delivery to your farm.
Made to Order: Please allow approximately 10–12 weeks from order confirmation to dispatch. Lead times may vary depending on current production schedules and availability.
*Indicative AUD. Your quote confirms the total cost, GST, freight and inclusions.
DIY PRODUCTION SYSTEM & TRAINING
You make your liquid fish and seaweed biofertiliser with our production system and guidance.
First Batch (Starter Package):
$1.80-3.50/L
Includes: First batch raw ingredients, assisted setup, 1:1 training, dedicated support over three batches, plus ongoing phone and email support.
Initial Investment: Varies according to system size and production requirements. A tailored quotation will confirm your setup costs and inclusions.
Every Batch After:
$1.00-1.20/L
Ongoing Production: Purchase the raw ingredients needed for each additional batch, with no recurring training/setup fee.
*Indicative AUD. Your quote confirms the total cost, GST, freight and inclusions.
SONIC Seaweed Biofertiliser — Suggested Rates
| Crop / System | Typical Rate or Dilution | Application |
|---|---|---|
| Seed inoculation | 1:80–1:150 dilution | Light seed coating before sowing |
| Seedlings / microgreens | 1:100–1:200 dilution | Foliar spray or soil drench during establishment |
| Cover crops | 2–5 L/ha | During establishment and early growth |
| Vegetables | 3–8 L/ha | During establishment and crop growth |
| Turf / lawns | 3–10 L/ha | During active growth and recovery after mowing |
| Vines | 4–8 L/ha | During flowering and fruit development |
| Fruit & nut trees | 5–10 L/ha | During active growth and flowering |
| Broadacre crops | 2–6 L/ha | During establishment and early growth |
| Fertigation | 1–5 L/ha equivalent | Through irrigation system as required |
| Grazing / pasture | 3–8 L/ha | During pasture growth and recovery after grazing |
Liquid Seaweed — Indicative Cost per Hectare
Costs shown are indicative product costs per hectare, per application, based on made-to-order pricing of $2.30–$3.90/L and ongoing DIY production costs of $1.00–$1.20/L. DIY costs exclude the one-off starter fee for initial setup and training. Your quote confirms that fee, GST, freight and inclusions.
Rates refer to undiluted product. See rates and methods.
| Product Rate | Made-to-Order Cost/ha | DIY Ongoing Cost/ha |
|---|---|---|
| 1 L/ha | $2.30–$3.90 | $1.00–$1.20 |
| 2 L/ha | $4.60–$7.80 | $2.00–$2.40 |
| 3 L/ha | $6.90–$11.70 | $3.00–$3.60 |
| 4 L/ha | $9.20–$15.60 | $4.00–$4.80 |
| 5 L/ha | $11.50–$19.50 | $5.00–$6.00 |
| 6 L/ha | $13.80–$23.40 | $6.00–$7.20 |
| 8 L/ha | $18.40–$31.20 | $8.00–$9.60 |
| 10 L/ha | $23.00–$39.00 | $10.00–$12.00 |
SONIC Liquid Seaweed Biofertiliser — Analysis
SONIC Liquid Seaweed is made from Australian kelp using cold fermentation and microbial cultures. The analysis below shows its mineral content and microbial counts from previous testing. Naturally sourced ingredients and fermentation contribute to batch variation. Results are a guide, rather than guaranteed specifications for every batch.
SONIC Liquid Seaweed Analysis
| Nutrient | Amount (mg/L) |
|---|---|
| Nitrogen (N) | 1040 |
| Phosphorus (P) | 100 |
| Potassium (K) | 1600 |
| Sulphur (S) | 700 |
| Calcium (Ca) | 800 |
| Magnesium (Mg) | 500 |
| Sodium (Na) | 700 |
| Iron (Fe) | < 50 |
| Manganese (Mn) | 3.6 |
| Zinc (Zn) | 2.7 |
| Copper (Cu) | 1 |
| Cobalt (Co) | 0.1 |
| Boron (B) | 5 |
| Molybdenum (Mo) | 0.2 |
| Selenium (Se) | 0.05 |
| Iodine (I) | 2.79 |
| Microbes | Amount (CFU/g) |
| Lactic Acid Bacteria | 4200000 |
| Total Active Fungi | 2000 |
| Yeasts | 2000000 |
Analysis sources: Mineral figures are from SONIC Natural Farming’s previous product analysis summary; Iodine: Environmental Analysis Laboratory, Southern Cross University, report dated 11 July 2025. Microbial counts: APAL amended report dated 2 July 2025, expressed in CFU/g.
Product Storage
SONIC Biological Products contain no artificial additives or preservatives.
Use within three months of the packaging date, which marks the completion of the batch. Follow the storage instructions and best-before date on the container. Keep out of direct sunlight.
Biological Products should not be stored in a diluted form.
Feed your crops with 100% natural Liquid Seaweed (Kelp) Fertiliser containing organic minerals, trace elements, vitamins, carbohydrates, amino acids, essential fatty acids, growth factors and anti-oxidants. With seaweed’s natural alginates, it also provides superior gelling properties that provide moisture holding abilities in the soil.
- Diverse Uses: Beneficial for mixed crops, natives, orchards, fruit trees, and pasture.
- Root Stimulation: Supports strong roots and early growth.
- 100% Biodegradable: Leaves no toxic residue in soil, requires no withholding period.
SONIC Liquid Seaweed Organic Fertiliser for plants is derived from Australian Durvillaea Potatorum (Bull Kelp), and made with beneficial microbe cultures. No fillers, additives or preservatives.
Fermented Seaweed vs Conventional Kelp Extracts — What’s the Difference?
You really can see the difference, just driving up the road. We’re happy, and it has actually saved us a lot of money on extra fertilisers.
SONIC LIQUID SEAWEED
More Than Just a Fertiliser
SONIC Liquid Seaweed Biofertiliser is made from 100% Australian Bull Kelp (Durvillaea potatorum), a natural source of minerals, trace elements and valuable organic compounds that support crop nutrition and soil biology.
Through biological fermentation, complex seaweed compounds are broken down into simpler forms, helping improve nutrient availability. The result is a nutrient-rich liquid kelp fertiliser that provides readily available plant nutrients while supporting healthy soil biological activity.
Whether you’re caring for pastures, vegetables, flowers, trees, or houseplants, incorporating Liquid Seaweed Biological Fertiliser into your regimen, it is an excellent way to give your plants the organic nutrition they need.
Why Choose Australian Bull Kelp?
SONIC Liquid Seaweed Biofertiliser is made from Australian Bull Kelp (Durvillaea potatorum), a large brown seaweed native to the cool, nutrient-rich waters of southern Australia, including Tasmania.
Naturally rich in minerals, trace elements, alginates and other organic compounds, Bull Kelp provides a valuable raw ingredient for agricultural biofertilisers. These naturally occurring compounds can contribute to plant nutrition and support soil biological processes.
Through our biological fermentation process, we transform Australian Bull Kelp into a nutrient-rich liquid concentrate, preserving valuable seaweed-derived compounds while producing additional organic acids and microbial metabolites.
The result is a locally sourced liquid kelp biofertiliser designed to complement existing fertiliser programs and support productive Australian farming systems.
5 ha Avocados at Kilburney Farm, Central Coast, NSW, using regenerative farming principals, GreenBlower Mulch and SONIC Liquid Fish and Seaweed Biological Fertiliser, (Above image).
If I see something once and something that dramatic, I know it’s got to be doing good.
How Does Liquid Seaweed Biological Fertiliser Work?
SONIC Liquid Seaweed (Kelp) Biological Fertiliser is a unique product that harnesses the power of both beneficial microbes and the natural chelating properties of seaweed. This combination works to release locked-up minerals in the soil, making them more readily available for plant uptake.
The key lies in the synergistic relationship between the microbes and the seaweed. The microbes help to break down organic matter, freeing up essential nutrients like nitrogen, phosphorus, and potassium. Meanwhile, the seaweed’s natural chelating ability binds to these nutrients, preventing them from being leached away or becoming unavailable to plants.
Boost Soil Health by Stimulating Beneficial Microbes
When applied to the soil, Liquid Seaweed Biological Fertiliser stimulates soil bacteria. An increase in biological activity in the soil has many benefits including increased soil fertility, strong growth in plants, and natural plant immunity.
See Article – ‘Top 7 Benefits of Using Seaweed in Agriculture’
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