Comparison: Best Organic Fish Fertilizer (Updated | Dec 1st)
If you’re looking to give your garden a natural boost, you’ve probably heard about organic fish fertilizer. But with so many options out there, how do you know which one’s truly the best? We’ve done the research, tested the top contenders, and compared their ingredients, effectiveness, and value so you don’t have to. Let’s dive into the top picks that’ll help your garden thrive.
- 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 yield boost: 1 Gallon Organic Fish Emulsion Fertilizer for Plants – Ideal Liquid Fish Fertilizer for Plants
- Best for fish-kelp fusion: GS Plant Foods Liquid Fish & Kelp Fertilizer (1 Gallon) – Organic Material Review Institute Listed Natural Plant Food for Home Gardens
- Best for wintergreen fresh: Alaska Fish Emulsion Fertilizer 5-1-1 Concentrate 1 Gallon (Packaging may vary)
- Best for high-nitrogen meal: Fish Meal – Organic Fish Fertilizer 8-6-0 (5 lbs)
- Best for vibrant garden blend: Neptune’s Harvest Fish & Seaweed Fertilizer 2-3-1 (36 Ounce)
- Best for odorless protein power: Neptune’s Harvest Fish Fertilizer 2-4-1
- Best for root-boost bone: Down To Earth All Natural Fertilizers Organic Fish Bone Meal – High Phosphorus Plant Food for Buds
- Best for compact bloom booster: Neptune’s Harvest Fish & Seaweed Fertilizer 2-3-1
Product Comparison: Best Organic Fish Fertilizer
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
1 Gallon Organic Fish Emulsion Fertilizer for Plants – Ideal Liquid Fish Fertilizer for Plants, Flowers, Fruits & Vegetables, 2-3-1 NPK – Sustainably Sourced and Hydrolyzed for Steady Growth
- ORGANIC FISH EMULSION FERTILIZER – Our liquid fish fertilizer is made from sustainably sourced fish emulsion and we use up all the parts that would otherwise go to waste. Using an environmentally conscious method, ingredients are refined fresh and 100% cold pressed to help retain all of the nutrients, vitamins, and amino acids needed to grow healthy plants.
- GROW PLANTS NATURALLY – This wonderfully organic alternative to synthetic fertilizer contains a 2-3-1 NPK ratio perfect for light and frequent applications. Promotes steady, healthy plant development throughout the growing season.
- ENRICHES SOIL – Helps build a strong foundation for your organic garden to thrive on! Use as an effective soil drench to improve fertility, structure, and encourage the growth of beneficial microorganisms like fungi in your garden’s soil.
- PRODUCE MORE – Get the most out of your fertilizer and your garden! This organic garden fertilizer helps to increase crop yields and flower blooms. Gentle enough to use as a foliar spray makes this the perfect fish fertilizer for plants, flowers, and vegetables.
- SMELL THE DIFFERENCE – This fertilizer smells like fish because it’s made from fish! Crafted with high-quality concentrated and undiluted hydrolyzed fish emulsion each bottle gives off a pungent fishy aroma. When compared, we see it like this – if it doesn’t smell, then it’s not real fish!
GS Plant Foods Liquid Fish & Kelp Fertilizer (1 Gallon) – Organic Material Review Institute Listed Natural Plant Food for Home Gardens, Lawns, and Vegetables
- ORGANIC MATERIALS REVIEW INSTITUTE LISTED FOR TRUSTED GARDEN CARE Certified by OMRI for use in organic growing, GS Plant Foods Liquid Fish & Kelp Fertilizer delivers reliable, natural nutrition for vegetables, lawns, flowers, and shrubs.
- SEA-AND-SOIL BASED NUTRITION Made from North Atlantic seaweed (Ascophyllum nodosum) and fresh fish hydrolysate, this liquid concentrate provides essential nutrients and trace minerals that help support healthy soil and plant development.
- IMPROVES SOIL MICROBIOLOGY & NUTRIENT UPTAKE Supports a thriving soil ecosystem that promotes strong root systems and efficient nutrient absorption — the foundation for resilient, productive plants.
- EASY-TO-USE CONCENTRATE FOR ALL PLANTS Mix 2 oz per gallon of water and apply as a foliar spray or soil drench every 2–4 weeks. Safe for use on vegetables, fruits, ornamentals, turf, and houseplants.
- MADE IN THE USA – SUSTAINABLY PRODUCED Proudly produced by GS Plant Foods as a licensed fertilizer manufacturer. No synthetic chemicals, additives, or fillers — just natural ingredients formulated for healthy home gardens and hobby farms.
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
Fish Meal – Organic Fish Fertilizer 8-6-0 (5 lbs)
- Organic Fish Meal – All Natural Fertilizer!
- Excellent Source of Nitrogen and Phosphorus!
- Stimulates beneficial microbes
- 5 pound bulk bag of Organic Fish Meal Fertilizer
- Fish Meal is a perfect early season Organic Fertilizer!
Neptune’s Harvest Fish & Seaweed Fertilizer 2-3-1 (36 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
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
Down To Earth All Natural Fertilizers Organic Fish Bone Meal – High Phosphorus Plant Food for Buds, Bulbs, Blooms, Flower Beds 4-12-0, 5 lb
- Water-Soluble Formula – Easily dissolves in water for quick absorption and efficient nutrient delivery directly to the root zone
- Targets Root Development – Formulated to enhance root growth, improving plant stability, nutrient uptake, and drought resistance
- Fast-Acting Nutrients – Provides immediate access to essential nutrients like nitrogen, phosphorus, and potassium where roots need them most.
- Ideal for Transplants & Seedlings – Great for jumpstarting young plants or helping transplants establish quickly in new soil.
- Improves Soil-Root Interaction – Encourages a healthy rhizosphere, boosting microbial activity and root-zone nutrient cycling.
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
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 picking an organic fish fertilizer?
Look at the NPK ratio, concentration, and whether the product includes additional ingredients like kelp or seaweed. Check for certifications such as OMRI listing, which confirms suitability for organic gardening. Also consider the form (liquid emulsion vs solid meal) and any odor or burn‑risk warnings.
How do the NPK ratios differ among the listed fish fertilizers?
The Central Garden Brands and Neptune’s Harvest products use a 2‑3‑1 ratio, ideal for balanced growth and frequent applications. Alaska Fish Fertilizer and the GS Plant Foods blend have a 5‑1‑1 ratio, providing higher nitrogen for leafy growth. The Fish Meal option offers an 8‑6‑0 ratio, delivering strong nitrogen and phosphorus for early‑season feeding.
Which products are low‑odor or deodorized, and does odor affect performance?
Alaska Fish Emulsion (B002RH0B26) is deodorized with natural wintergreen, making it more pleasant for indoor use. Neptune’s Harvest claims a cold‑process that reduces smell, while most pure fish emulsions, like the 1‑gallon organic fish emulsion, have a strong fishy scent that indicates real fish content. Odor does not impact nutrient value, but a milder smell can improve the user experience.
What gives the best value per ounce or gallon among these options?
The 1‑gallon organic fish emulsion (B09FZTPQJL) provides a large volume at a competitive price, especially for frequent applications. Alaska’s 115‑oz OMRI‑listed fertilizer (B0DQ2LNX35) offers a mid‑size container with a higher nitrogen ratio, useful for faster growth. For bulk needs, the 5‑lb Fish Meal (B07RZ9FTH9) delivers a high nutrient concentration at a lower cost per pound.
Why is OMRI listing important, and which products have it?
OMRI listing verifies that a fertilizer meets organic standards and can be used in certified organic gardens. Both Alaska Fish Fertilizer (B0DQ2LNX35) and GS Plant Foods Liquid Fish & Kelp (B00BBLMXVQ) carry this certification, giving confidence to organic growers. Products without OMRI listing may still be natural but lack official organic verification.
Should I choose a liquid emulsion or a solid fish meal for my garden?
Liquid emulsions, like Central Garden Brands and the 1‑gallon organic fish emulsion, are easy to mix, provide quick nutrient uptake, and work well as foliar sprays or soil drenches. Solid fish meal offers a slow‑release nitrogen source, ideal for long‑term feeding and early‑season soil amendment. Your choice depends on whether you need rapid results (liquid) or a lasting nutrient reservoir (solid).
How often should I apply these fish fertilizers, and does concentration affect frequency?
Most liquid emulsions recommend application every 2–4 weeks, diluted according to label instructions; higher‑concentration products like the 5‑1‑1 concentrates can be applied less frequently. Fish meal is typically worked into the soil once per growing season, providing nutrients over several months. Adjust frequency based on plant response and soil test results.
Do added ingredients like kelp or seaweed provide extra benefits?
Yes, products that combine fish with kelp or seaweed, such as GS Plant Foods Liquid Fish & Kelp, supply additional trace minerals, hormones, and micronutrients that enhance root development and stress tolerance. These blends can improve soil microbiology and nutrient uptake compared to pure fish emulsions. If you want a more comprehensive nutrient profile, choose a formula that includes seaweed.