Comparison: Best Fish On Fertilizer (Updated | Dec 1st)
Ever wondered if your garden could thrive with a little help from the sea? In this comparison, we’ll dive into the best fish fertilizers on the market—weighing smell, nutrient content, ease of use, and real results. Whether you’re growing tomatoes or tending a flower bed, we’ve tested the top options so you can feed your soil with confidence—and maybe save a few scraps for dinner.
1 Gallon Organic Fish Emulsion Fertilizer for Plants – Ideal Liquid Fish Fertilizer for Plants
Sustainable Yield Booster
- Best for omri-certified 5-1-1: Alaska Fish Fertilizer OMRI Listed 5-1-1
- Best for vitamin-rich organic: CENTRAL GARDEN BRANDS 100099247 Fish Emul Fertilizer
- Best for wintergreen deodorized: Alaska Fish Emulsion Fertilizer 5-1-1 Concentrate 1 Gallon (Packaging may vary)
- Best for sustainable yield booster: 1 Gallon Organic Fish Emulsion Fertilizer for Plants – Ideal Liquid Fish Fertilizer for Plants
- Best for deep green growth: Fertilome (10612) Fish Emulsion Fertilizer 5-1-1 (32 oz)
- 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 seaweed veg boost: Neptune’s Harvest Fish & Seaweed Fertilizer 2-3-1
- Best for odorless cold-processed: Neptune’s Harvest Fish Fertilizer 2-4-1
- Best for large odorless formula: Neptune’s Harvest Fish Fertilizer 2-4-1
- Best for aquarium plant nutrient: API LEAF ZONE Freshwater Aquarium Plant Fertilizer 8-Ounce Bottle
Product Comparison: Best Fish On Fertilizer
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
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 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
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!
Fertilome (10612) Fish Emulsion Fertilizer 5-1-1 (32 oz)
- Develops deep green foliage, vigorous root systems and a solid plant structure
- Derived from fish soluble, can be used from indoor and outdoor. Can be used on plants and trees.
- Mixes with water and can be used by any convenient method of application. Shake well before use.
- 5-1-1 Fertilizer contains 5% Nitrogen, 1% Phosphate and 1% Soluble Potash.
- For plants mix 1-2 tbsp per 1 gal of water. For trees mix 4 tbsp per gal of water.
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.
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
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
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
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
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 NPK ratio is ideal for a general‑purpose fish fertilizer?
Most all‑purpose fish fertilizers use a 5‑1‑1 or 2‑3‑1 ratio, which provides a balanced supply of nitrogen for leafy growth, phosphorus for root development, and potassium for overall vigor. The 5‑1‑1 ratio (e.g., Alaska Fish Fertilizer) is higher in nitrogen and works well for rapid foliage, while 2‑3‑1 (e.g., the 1‑gallon organic fish emulsion) offers a gentler, more frequent feeding schedule. Choose the ratio that matches your plant’s growth stage and the frequency you plan to apply.
How do the odor levels compare between the different fish fertilizers?
Traditional fish emulsions, such as Alaska Fish Emulsion, often have a noticeable fishy smell, though some products are deodorized with wintergreen. Neptune’s Harvest uses a cold‑process that retains nutrients while minimizing odor, and the 2‑4‑1 formula advertises “no unpleasant odor.” If scent is a concern for indoor use, opt for deodorized or low‑odor formulations like the Central Garden Brands fish emulsion or Neptune’s Harvest.
Is an OMRI‑listed fish fertilizer worth the extra cost?
OMRI‑listed products, like Alaska Fish Fertilizer and GS Plant Foods Liquid Fish & Kelp, are certified for organic gardening and meet strict standards for natural ingredients. This certification can be valuable for growers who need to maintain organic certification for their produce. While they may be slightly pricier, the assurance of compliance and the reputation of the brand often justify the cost.
Which fish fertilizer is best suited for indoor houseplants?
For indoor plants, a low‑odor, easy‑mix formula is ideal. Central Garden Brands 1‑quart Fish Emulsion and the deodorized Alaska Fish Emulsion both claim no burn and minimal scent, making them safe for indoor environments. Mix the recommended amount with water and apply as a soil drench or foliar spray to avoid strong odors inside the home.
What are the practical differences between liquid fish emulsions and concentrated fish fertilizers?
Liquid emulsions, such as the 1‑gallon Organic Fish Emulsion, are ready‑to‑dilute and provide quick nutrient availability, but they require more frequent applications. Concentrated formulas like the 5‑1‑1 Alaska Fish Fertilizer (115 oz) are more economical per use and can be stored longer, though they need careful dilution to avoid over‑feeding. Choose emulsions for fast results and concentrates for larger gardens where cost per acre matters.
Can I safely use fish fertilizer on vegetables and fruit trees?
Yes, fish fertilizers are safe for edible plants because they are derived from natural fish proteins and contain no synthetic chemicals. Products labeled “100 % organic” (e.g., Central Garden Brands) and those with OMRI certification are especially suitable for vegetable gardens and fruit trees. Follow the label’s dilution rates to prevent nutrient excess and ensure optimal fruit quality.
How does value compare between gallon‑size and smaller containers?
Gallon‑size options, such as the 1‑gallon Organic Fish Emulsion and GS Plant Foods Liquid Fish & Kelp, typically offer a lower cost per ounce and are best for larger landscapes or frequent applications. Smaller containers like the 18‑ounce Neptune’s Harvest provide convenience for trial use or small gardens but have a higher price per ounce. Consider the size of your garden and how often you plan to fertilize when weighing upfront cost against long‑term value.