Comparison: Best Fish Fertilizer For Plants (Updated | Nov 11th)
If your garden’s looking a little under the weather, the fix might just come from the sea. But with so many options out there, how do you know which one’s truly the best? Let’s find your garden’s new favorite feed.
- Best for vitamin-rich boost: CENTRAL GARDEN BRANDS 100099247 Fish Emul Fertilizer
- Best for omri certified blend: Alaska Fish Fertilizer OMRI Listed 5-1-1
- Best for seaweed-enhanced growth: Neptune’s Harvest Fish & Seaweed Fertilizer 2-3-1
- Best for wintergreen fresh formula: Alaska Fish Emulsion Fertilizer 5-1-1 Concentrate 1 Gallon (Packaging may vary)
- Best for cold-processed purity: Neptune’s Harvest Fish Fertilizer 2-4-1
- Best for aquarium plant power: API LEAF ZONE Freshwater Aquarium Plant Fertilizer 8-Ounce Bottle
- Best for salmon nutrient complete: Fish Emulsion Fertilizer
- Best for hydrolyzed macro‑micro: Organic Hydrolyzed Liquid Fish Fertilizer by GS Plant Foods (1 Gallon)
- Best for large‑scale purity: Neptune’s Harvest Fish Fertilizer 2-4-1
- Best for omega‑rich salmon: Bloom City Organic Wild Fish Fertilizer and Plant Supplement
Product Comparison: Best Fish Fertilizer For Plants
CENTRAL GARDEN BRANDS 100099247 Fish Emul Fertilizer, 1 Quart
- Promotes healthy plant growth with 11 vitamins
- Can be used on all indoor and outdoor plants
- 100-percent organic
- Stimulates microorganisms
- Does not burn
Alaska Fish Fertilizer OMRI Listed 5-1-1, 115 oz
- Fish-based fertilizer for use in vegetable, fruit, and flower gardens
- Excellent for use on flowers, trees, and other plants
- OMRI listed
- For organic gardening
- Great for all indoor and outdoor plants
- NPK 5-1-1 fish emulsion fertilizer
- Fish has been used as a natural source of plant nutrients for centuries
- Easy to use, just mix with water
Neptune’s Harvest Fish & Seaweed Fertilizer 2-3-1, 18 Ounce
- Grow a beautiful vegetable garden
- Flowers and foliage will be stronger and more colorful
- Blooms will be more plentiful, fragrant and longer lasting
- Easy to mix and apply by hand, sprayer, or drip line
Alaska Fish Emulsion Fertilizer 5-1-1 Concentrate 1 Gallon (Packaging may vary)
- Will Not Burn
- Great for all plants
- Deodorized with Natural Wintergreen
- 5-1-1 fertilizer is an excellent source of organic plant nutrients
- Fish Fertilizer
Neptune’s Harvest Fish Fertilizer 2-4-1, 18 Ounce
- Neptune’s Harvest is an organic fertilizer made from fresh north Atlantic fish
- It is made by a unique cold process that protects the vitamins, amino acids, enzymes and growth hormones
- It also contains all the micro and macro nutrients naturally found in fish
- Unlike fish emulsions, Neptune’s Harvest retains the fish proteins and oils and has no unpleasant odor
API LEAF ZONE Freshwater Aquarium Plant Fertilizer 8-Ounce Bottle
- Product Type: ARTIFICIAL PLANT
- Package length: 19.558 cm
- Package width: 3.048 cm
- Package height: 4.572 cm
Fish Emulsion Fertilizer, Complete Fish Emulsion Plant Food, 8 oz (250mL)
- Complete fish fertilizer for thriving plants
- Helps growth with natural harvest salmon nutrients
- Easy-to-follow care instructions included
- Made in the USA
Organic Hydrolyzed Liquid Fish Fertilizer by GS Plant Foods (1 Gallon)
- OMRI ORGANIC LISTED HYDROLYZED FISH FERTILIZER: GS Plant Foods Organic Liquid Fish is an all-natural high quality fresh fish liquid fertilizer that gives excellent plant growth, rebuilds soil, and offers higher production yields. Our fish fertilizer will help stimulate growth and improve plant health and color. Tremendously beneficial for soil quality and improved rooting, this organic fish fertilizer can be applied to any type of soil or plant without concern for waste or harmful chemicals.
- PACKED WITH MACRO & MICRO NUTRIENTS: Our proprietary and all-natural fish fertilizer provides much more than N-P-K (Nitrogen, Phosphorus and Potassium) found in synthetic fertilizers. This fish plant fertilizer provides a comprehensive mix of macro & micro nutrients, minerals, peptides, proteins, and calcium, all in a usable form perfectly suited for maximum efficiency of uptake for your plants. The fish plant food fertilizer stimulates water penetration and increases nutrient assimilation.
- OPTIMAL PLANT GROWTH & HEALTH AT HOME OR COMMERCIALLY: Used in low concentrations, liquid fish fertilizer organic acts as an efficacious growth promoter. GS Plant Foods organic hydrolyzed fertilizer promotes growth of healthy bacteria. It is used extensively on a commercial basis, as well as at home as an organic soil conditioner. The end result is a powerfully effective, organic fertilizer and soil supplement that contains no chlorine or heavy metals. It is great for everything that grows!
- WORKS SYNERGISTICALLY WITH ALL FERTILIZERS:This liquid fish fertilizer is among the highest quality plant food products that you can get. It works synergistically with all fertilizers especially with a high quality liquid kelp fertilizer such as GS Plant Foods Organic Liquid Kelp. Use fish fertilizer on lawns, vegetables, fruits, trees & shrubs, seedlings and transplants as a regular healthful maintenance program to experience healthier plants with stronger, and more developed root systems.
- EASY TO APPLY FOR NATURAL GREAT RESULTS: Apply hydrolyzed fish fertilizer to improve specific growth stages. Apply generously to soil or as a foliar feed until leaves are wet, top and bottom. For lawns, one gallon of fertilizer mixed with 30-40 gallons of water will cover ¼ acre. Feed lawn every 4 weeks. Trees and shrubs use 4 oz per gallon of water. Feed by boring small holes 1 to 2 feet away from the root ball. Fill holes with solution. For best results, foliar feed early or late in the day.
Neptune’s Harvest Fish Fertilizer 2-4-1, 36 Ounce
- Neptune’s Harvest is an organic fertilizer made from fresh north Atlantic fish
- It is made by a unique cold process that protects the vitamins, amino acids, enzymes and growth hormones
- It also contains all the micro and macro nutrients naturally found in fish
- Unlike fish emulsions, Neptune’s Harvest retains the fish proteins and oils and has no unpleasant odor
Bloom City Organic Wild Fish Fertilizer and Plant Supplement, Great for Roots and Soil, Made from Sustainable Salmon, 1/2 Pint (8 oz)
- FROM SUSTAINABLE ALASKAN SALMON: Great for Soil and Plants, for indoor and outdoor use.
- CONTAINS SALMON EMULSION AND SALMON OIL: Very high in omega 3 Fatty Acids for Plants. More Amino Acids than any other brand.
- SMELLS LIKE FISH: You know this is the good stuff, because is really really smells like ocean and fish.
- HIGHEST QUALITY, MOST POTENT, BEST VALUE, BIGGEST YIELD: Bloom City’s ingredients are better for plants, better for you, and better for the planet. Simply the best choice for the conscientious grower.
- FORMULATED AND MADE IN THE USA: Designed by botanists and plant chemists in Seattle, Washington. Bloom City chooses only the highest quality ingredient sources and manufacturing methods to create the world’s best craft growing nutrient systems.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.
Buying Guide
FAQs
What key factors should I compare when choosing a fish fertilizer for my garden?
Look at the N-P-K ratio, organic certification (such as OMRI listing), and any added micronutrients. Consider the product’s form—liquid emulsion, concentrate, or powdered—and how easy it is to mix and apply. Also check for odor control features and whether the formula is safe for both indoor and outdoor plants.
How does a 5-1-1 ratio fertilizer differ from a 2-4-1 or 2-3-1 blend?
A 5-1-1 blend is higher in nitrogen, promoting rapid leaf and stem growth, which is ideal for leafy vegetables and fast‑growing annuals. A 2-4-1 or 2-3-1 ratio provides more phosphorus, encouraging strong root development and flower production, making them better for fruiting plants and blooming gardens. Choose the ratio that matches the growth stage you want to emphasize.
Is there a noticeable advantage to using a cold‑processed fish fertilizer like Neptune’s Harvest over standard emulsions?
Cold‑processed fertilizers retain more vitamins, amino acids, enzymes, and growth hormones because the fish proteins and oils aren’t broken down by heat. This can result in richer foliage color and stronger root systems. Additionally, many cold‑processed products have reduced odor compared to traditional fish emulsions.
Do OMRI‑listed fish fertilizers offer any extra benefits for organic gardeners?
OMRI listing confirms that the product meets strict organic standards, allowing it to be used in certified organic gardening without risking compliance issues. These fertilizers are typically free from synthetic chemicals and heavy metals, ensuring a cleaner soil environment. They also often include natural microorganisms that improve soil health.
How do price and concentration affect the overall value of a fish fertilizer?
Higher‑concentration products, such as gallon‑size concentrates, may have a higher upfront cost but provide more applications per purchase, lowering the cost per use. Smaller bottles are convenient for trial or limited‑area use but can become expensive if you need frequent applications. Calculate the total amount of fertilizer needed for your garden size to determine the most cost‑effective option.
Can fish fertilizers be safely used on indoor houseplants?
Yes, most fish fertilizers are labeled safe for indoor use, especially those formulated to be non‑burning and low‑odor. Dilute the product according to the manufacturer’s instructions and apply it as a soil drench or light foliar spray. Avoid over‑application, which can lead to excess moisture and root rot in confined indoor pots.
What extra features should I look for if I want a fertilizer that also improves soil biology?
Products that mention stimulating microorganisms, containing organic matter, or being hydrolyzed often promote beneficial soil microbes. These additives help break down organic material, improve nutrient uptake, and enhance overall soil structure. Choosing a fertilizer with these traits can lead to healthier, more resilient plants over time.