If you're looking for a way to boost the health and productivity of your garden, you might want to consider fish hydrolysate. This organic and sustainable fertilizer is made from fresh fish and provides a range of benefits for your plants and soil.
In this blog post, we'll take a closer look at the benefits of fish hydrolysate and why Ocean Grown Fish Hydrolysate is the best choice for gardeners who want a healthy and productive garden.
Fish Hydrolysate vs Fish Emulsion: What’s the Difference?
Fish hydrolysate is often confused with fish emulsion, but they’re made very differently — and that difference matters for your soil.
Fish hydrolysate is produced using a cold, enzymatic process. The whole fish (or fish by-products) is broken down naturally, without heat. This helps preserve beneficial compounds like amino acids, natural oils, enzymes, and trace minerals that soil microbes love.
Fish emulsion, on the other hand, is typically heat-processed. During this process, oils are often removed and some heat-sensitive nutrients are damaged or lost. While fish emulsion can still provide nitrogen, it generally offers less biological value for building long-term soil health.
If you’re focused on feeding the soil food web — not just the plant — fish hydrolysate is the more complete, biology-friendly option.
How Fish Hydrolysate Is Stabilised (and Why It Matters)
Because fish hydrolysate is cold-processed and biologically active, it needs to be stabilised to stay fresh and effective.
Most high-quality fish hydrolysates are stabilised using gentle acids (often phosphoric acid) to prevent spoilage while keeping the beneficial biology intact. This stabilisation helps:
-
Extend shelf life
-
Reduce unwanted fermentation
-
Maintain nutrient availability
Cold-processed products can smell “fishy” — that’s normal — but they shouldn’t smell rotten or sulphur-like. Proper stabilisation ensures the product remains safe, consistent, and easy to use in the garden.
Once opened, storing your fish hydrolysate in a cool, shaded place and sealing the lid tightly will help keep it in top condition.
The Benefits of Fish Hydrolysate
Organic and Sustainable Fertilizer
One of the biggest benefits of fish hydrolysate is that it is an organic and sustainable fertilizer. Unlike synthetic fertilizers, which are often made from non-renewable resources and can harm the environment, fish hydrolysate is made from a renewable resource and is environmentally friendly.
Compared to synthetic fertilizers, fish hydrolysate provides a range of benefits for your plants and soil. For example, it promotes healthy soil, which in turn promotes healthy plants. Additionally, it doesn't leave behind harmful chemicals that can build up in the soil and harm the environment over time.
Promotes Soil Health
Enhances Plant Growth
What About NPK? Understanding Bioavailable Nutrition
If you’re used to comparing fertilisers by NPK alone, fish hydrolysate might look modest on paper.
Fish hydrolysate typically has a low to moderate NPK (for example, around 2-3% nitrogen), but that’s only part of the story. What makes it powerful is how available those nutrients are.
The nutrients in fish hydrolysate are bound to amino acids and organic compounds, making them easier for soil microbes and plant roots to access. Instead of pushing rapid, artificial growth, fish hydrolysate supports steady, balanced nutrition that works in harmony with living soil.
In short: it’s not about force-feeding plants — it’s about feeding the system that feeds the plants.
Is Fish Hydrolysate Safe? What to Look For
As gardeners become more informed, questions around purity and safety are completely valid.
Quality fish hydrolysate should be made from responsibly sourced fish or fish by-products and processed in a way that minimises contaminants such as heavy metals, PCBs, or PFAS.
When choosing a fish hydrolysate, look for:
-
Transparent sourcing
-
Proper filtration and stabilisation
-
Clear labelling and organic certification where possible
A well-made fish hydrolysate supports soil health without introducing unwanted residues — making it suitable for food gardens, native plants, and long-term soil building.
Why Choose Ocean Grown Fish Hydrolysate?
Unique Production Process
High-Quality Ingredients
Ocean Grown Fish Hydrolysate is made from fresh, sustainable, and ethically sourced fish. It's also triple-filtered for purity and easy application, so you can be sure you're getting the best possible product for your garden.
Proven Results
Ocean Grown Fish Hydrolysate has been proven to support healthier, more productive plants. It enhances soil health and structure, increases resistance to pests and disease, and helps your plants reach their full potential.
How to Use Fish Hydrolysate
Application Methods
Fish hydrolysate can be applied through various methods, including as a soil conditioner through a fertigation system, as a foliar spray, or added to compost piles or worm farms
Soil conditioner through a fertigation system
Fertigation is the process of injecting fertilizer into an irrigation system. Fish hydrolysate can be added to the irrigation system, and when plants are watered, the fertilizer is distributed evenly to the roots. This is a cost-effective and efficient method to apply fish hydrolysate.
A foliar spray is the application of liquid fertilizer directly onto the leaves of the plant. This method is beneficial for providing the plant with an immediate source of nutrients, which is especially important during times of stress or growth.
Added to compost piles or worm farms
Adding fish hydrolysate to compost piles or worm farms helps to speed up the decomposition process and improve the overall quality of the compost. This method is especially beneficial for vegetable gardens, as it helps to produce nutrient-rich soil for the plants to grow in.
Application Rates & When to Use Fish Hydrolysate
Fish hydrolysate is gentle and forgiving, but correct dilution helps you get the best results.
General soil drench:
-
5–10 mL per litre of water
Seedlings & transplants:
-
Use the lower end of the range to reduce stress and support root establishment
Vegetables, flowers & fruit trees:
-
Apply every 2–4 weeks during active growth
Foliar sprays:
-
Dilute further (around 2–5 mL per litre) and apply in the early morning or late afternoon
Fish hydrolysate works best as part of a regular soil-building routine rather than a one-off fix.
Tips for Using Fish Hydrolysate
To get the most out of fish hydrolysate, here are some tips to keep in mind:
Avoid using in direct sunlight to prevent leaf burn
Fish hydrolysate can cause leaf burn if applied in direct sunlight. It is best to apply the fertilizer in the early morning or late evening when the sun is not as intense.
Dilute with water for best results
Diluting the fish hydrolysate with water before application can help to prevent burning the plant and ensure that the nutrients are distributed evenly. Follow the product instructions for the proper dilution rate.
Store in a cool, dry place away from direct sunlight
Fish hydrolysate should be stored in a cool, dry place away from direct sunlight to prevent the breakdown of nutrients. If the product is not stored properly, the efficacy of the fertilizer may be reduced.
A More Sustainable Way to Feed Your Garden
Fish hydrolysate plays an important role in sustainable gardening.
Many products are made using fish by-products that would otherwise go to waste, turning them into valuable inputs for soil regeneration. This supports a more circular approach to agriculture — where nutrients are reused rather than discarded.
When sourced responsibly, fish hydrolysate helps close the loop between land and sea, supporting healthier soils without relying on synthetic fertilisers.
How to Tell It’s Working
You don’t need lab tests to see the benefits of fish hydrolysate — your garden will show you.
Common signs include:
-
Deeper green foliage
-
Stronger, more consistent growth
-
Improved flowering and fruit set
-
Soil that smells rich and earthy
For advanced growers, occasional soil health testing or plant sap analysis can provide deeper insight, but for most gardeners, visual plant health and soil structure are the best indicators.
Frequently Asked Questions (FAQs)
Is fish hydrolysate safe for my plants and soil?
Yes, fish hydrolysate is a safe and natural fertilizer that can be used on all types of plants and soil. It is an organic and sustainable alternative to synthetic fertilizers, and it promotes overall soil health and plant growth.
How often should I apply fish hydrolysate?
The frequency of fish hydrolysate applications will depend on several factors, including the type of plants, soil quality, and weather conditions. It is recommended to follow the product instructions for the proper application rate and frequency.
Can I use fish hydrolysate on edible plants?
Yes, fish hydrolysate is safe to use on all types of plants, including edible ones. In fact, it is a natural and organic way to promote healthy growth and improve soil quality.
Will fish hydrolysate attract unwanted pests?
No, fish hydrolysate is not known to attract unwanted pests. In fact, it can help to repel some pests due to its strong taste and oil content.
What are the benefits of using Ocean Grown Fish Hydrolysate?
Ocean Grown Fish Hydrolysate is made using a unique cold enzymatic process that preserves the integrity of the nutrients, ensuring that you're getting the highest quality product possible. It's also made from fresh, sustainable, and ethically sourced fish and is triple-filtered for purity and easy application. Using Ocean Grown Fish Hydrolysate has been proven to support healthier, more productive plants, enhance soil health and structure, increase resistance to pests and disease, and help your plants reach their full potential.
Does fish hydrolysate smell?
Yes — a mild fishy smell is normal. A strong rotten or sulphur smell may indicate spoilage.
Will it attract pests?
When diluted correctly and watered into the soil, it shouldn’t attract pests. Avoid leaving undiluted product on surfaces.
Can it burn plants?
Fish hydrolysate is gentle, but over-application can stress plants. Stick to recommended dilution rates.
Can I use it in irrigation systems?
Only if the product is well-filtered. Flush lines after use to avoid clogging.
Can I mix it with other inputs?
Yes — fish hydrolysate pairs well with seaweed extracts, compost teas, and microbial inoculants.
About the Author
