Fish Fertilizer For Plants: Everything You Need To Know

Being a nutrient-rich emulsion from nature, fish fertilizer (often called fish emulsion) is excellent for farmers who want to grow their farm efficiently and organically.

Today’s post will detail why you should use fish fertilizer and how to apply it to your plants.

Plus, we will give you some notices and answer the most frequently asked questions related to the topic, so keep going with us.

What Is Fish Fertilizer?

Fish fertilizer is made from both whole fish and byproducts of the fishing industry. It is available in 3 types: fish meal, fish emulsion, and fish hydrolysate. Fish emulsion is the most popular form, so people often use this name for this fertilizer.

Those forms contain high nitrogen, phosphorus, potassium, and trace minerals such as calcium, iron, and sodium.

Using fish fertilizer to feed vegetables isn’t something new. Centuries ago, native American farmers placed small fish in the soil as preparation for growing corn.

The best way to use liquid fish fertilizer in your summer house plants:

How Is Fish Fertilizer Made?

First, fish and carcass products are finely ground into a slurry. Then the mixture is processed to separate fish oil and fish meal.

The rest becomes a fish emulsion after straining to remove any solids last. Before packaging, some sulfuric acid will be added to the emulsion to avoid growing microbes.

Benefits Of Fish Fertilizer

Nurturing plants

With an intense N-P-K ratio of about 5:1:1 or 5:2:2 as the primary nutrients and various trace minerals as the secondary supply, fish fertilizer provides vital resources for the plants to thrive and resist diseases.

In detail, nitrogen works on the leaves, phosphorus helps the roots, and potassium regulates nutrition. As for minerals, they play an essential role in drought protection and producing growth hormones.

See also  Monstera Siltepecana: Care And Growing Guide

Enhancing soil structure

Fish fertilizer improves soil by encouraging the activity of micro-organisms. As they process emulsion’s nutritions for plants and then clean the dirt when moving, they help the ground become aerated and get more organic matter.

Besides, the high nitrogen level in fish fertilizer helps increase soil microbes, resulting in healthy and organic soil. So, good soil, good plants!


As an organic product, fish fertilizer benefits the environment in such ways:

  • Feed the microbes.
  • Enhance soil texture.
  • Sustainable by slow release.
  • Safer for farmers by containing fewer chemical elements.
  • Make use of the leftover parts from the fish industry, which otherwise is wasted.

Which Form Of Fish Fertilizers Matches My Need?

As fish-based organic fertilizers, all of them are considered all-purpose nutrients for plants during the growing season. But some plants benefit from specific fish fertilizers.

  • Fish emulsion: This is excellent for leafy green vegetables, thanks to its high level of nitrogen. It is also the favorite lawn fertilizer in the early spring.
  • Fish meal: This fertilizer releases nutritions gradually, so it is the top-notch choice to feed the microbes and re-innovate soil. It’s the best for heavy feeders like corn, tomatoes, and pepper.
  • Fish hydrolysate: This one is good to stimulate flowering sites and increases fruit and flower size. Besides, it’s a fantastic food for microbes. It can be used ideally as soil fertilizer, added to compost piles or worm farms.

Notes: Fish fertilizers that are non-deodorized may smell bad like fish or even worse. So, be careful to choose the deodorized one when applying for houseplants.

For example, you would want the low-odor and dust-free one, such as dry Alaska for indoor plants.

See also  Top 5 Easy Fruits To Grow For Making Desserts

How To Apply Fish Fertilizer?

Fish liquid fertilizers

Fish liquid fertilizers can be used as a foliar spray or a soil drench. You should apply the fertilizer twice a week to get the best result.

To prepare, you will need:

  • A bottle of emulsion.
  • A can/bucket/sprayer to water plants.

Mix 2 – 3 tbsp of fish emulsion with 1 gallon (4 liters) of water for about 25 square feet of soil (recommend). To feed plants, you can water them overhead to use as a foliar spray or drench the ground to help the roots get more nutrition.

Fish dry fertilizer

Most fry fertilizer can be applied to the soil or used as a foliar spray but is less effective than the liquid forms.

  • To use as a sprayer, use 2 tbsp of fish meal per gallon of water and work as the liquid fish fertilizers.
  • To use as a fertilizer for existing plants, spread the pellets/meal on the ground and water well for them to seep into the soil.
  • To use as a soil regenerator/preparation, apply it about one week before growing seasons. Then, mix it into the soil and water well to let living organisms work.

Notes: Above are our suggestions based on general uses. When you get a fertilizer, the best way to make your fertilizer mixture is to read the product’s manual for the exact guidance.

Can fish fertilizer be made at home?

The answer is yes. You can make fish fertilizer at home with the fish itself or add some materials like crab or seaweed for more nutrient-rich.

Materials needed:

  • A bucket with a lid.
  • Whole fish or fish scraps.
  • Organic matter such as leaf litter.
  • Molasses and seaweed (not mandatory)

Step by step:

  • Fill the bucket up to ⅔ by layering fish and organic matter in equal parts. Add some molasses and seaweed if you have them.
  • Add water to fill the bucket. Place the lid, keep the mixture out of the sun and stir them every several days.
  • After a few weeks, take the liquid part as your fish emulsion fertilizer. The rest can be reused to make another batch or put into the compost pile or worm bin as the fish hydrolysate.
See also  The Art of Floristry: How to Make a Beautiful Bouquet at Home

For more visual guidance, watch this video to learn how to make a fish emulsion with crabs by yourself.

What to notice when using fish fertilizer?

If the soil is high in nitrogen already, applying too much fish emulsion will cause nitrogen burn that harms growth, resulting in desiccated plants.

To know the status of your garden, use a home soil test or go to a professional for help.

Is organic fish fertilizer better than other organic ones?

Research has shown that it is not better or worse than any other organic fertilizers, compost, manure, or coffee grounds.

What makes a fertilizer efficient is an N-P-K ratio in which nitrogen is considered the most critical nutrient. The nitrogen level in fish fertilizer goes around 2 – 5% that is similar to other types.

Does fish fertilizer attract animals?

As mentioned earlier, some non-deodorized products have the smell of fish, and they can attract animals like pets or wildlife. This happens with homemade fish fertilizer, too.

If you are feeding your plants with those products, consider applying them deeper in the ground so that animals won’t notice their scents.


We’ve gone through the most important things you need to know before using fish fertilizer for plants. In a nutshell, this is an ideal way to grow your garden productively, organically, and eco-friendly.

Fish Fertilizer For Plants: Everything You Need To Know
Photo of author

Jill Sandy

I am a sustainable focus gardener. I love decorating my home backyard with beautiful landscape design and creative garden care techniques I develop myself.

Leave a Comment