Fish emulsion fertilizer delivers a fast nitrogen boost that makes leafy vegetables grow noticeably within days of application. This liquid organic fertilizer has an NPK ratio of approximately 5-2-2, making it one of the strongest natural nitrogen sources available to home gardeners. Filipino gardeners particularly benefit from fish emulsion because the Philippines produces abundant fish processing waste that feeds the local production of this product.
What Is Fish Emulsion?
Fish emulsion is a thick, concentrated liquid made from whole fish or fish processing waste. Manufacturers heat the raw material, press out oils, and stabilise the remaining liquid. The result contains nitrogen, phosphorus, potassium, calcium, magnesium, and trace minerals. Unlike synthetic fertilizers, fish emulsion also provides amino acids and beneficial bacteria that improve soil health over time.
The product comes in bottles that you dilute with water before applying. A single 500-millilitre bottle makes 15 to 30 litres of diluted fertilizer solution, lasting most home gardeners several months.
How to Use Fish Emulsion
Soil Drench Method
Mix 15 to 30 millilitres of fish emulsion per litre of water. Water the soil around plant bases with this solution. Apply to moist soil to prevent root burn. Use every 2 weeks during active growth. This method delivers nutrients directly to the root zone where plants absorb them most efficiently.
Foliar Spray Method
Dilute fish emulsion to half the soil drench strength (8 to 15 millilitres per litre). Spray onto leaf surfaces in the early morning when stomata are open. Plants absorb foliar-applied nutrients faster than soil-applied ones. This method provides quick nutrient correction for visibly deficient plants. Avoid spraying in direct midday sun.
Seedling Starter
Use a very dilute solution (5 millilitres per litre) to water seedlings after their first true leaves appear. The gentle nitrogen boost promotes strong early growth without overwhelming young root systems. Apply once a week until seedlings are ready for transplanting.
Best Plants for Fish Emulsion
- Leafy vegetables. Kangkong, pechay, lettuce, and spinach respond dramatically to the nitrogen in fish emulsion. Expect noticeably larger leaves within a week of application.
- Herbs. Basil, mint, parsley, and spring onion produce more abundant foliage with regular fish emulsion feeding.
- Foliage plants. Aglaonema, pothos, ferns, and philodendron develop richer leaf colour and faster growth.
- Lawns. Dilute fish emulsion applied to carabao grass and frog grass produces deeper green colour within days.
Avoid fish emulsion for: flowering plants during bloom stage (excess nitrogen suppresses flowers) and fruiting vegetables after flowers appear (switch to a high-phosphorus fertilizer instead).
Alternatives to Fish Emulsion
- Vermicast tea. Balanced liquid organic feed without the smell. Soak vermicast in water for 24 hours.
- Fermented plant juice. Made from fast-growing plant shoots fermented with brown sugar. Provides growth hormones and mild nutrients.
- Banana peel water. Potassium-rich liquid for flowering and fruiting. Complements fish emulsion well.
- Seaweed extract. Rich in micronutrients and growth stimulants. Works as a foliar spray alongside fish emulsion.
Where to Buy in the Philippines
- Agricultural supply shops. Carry local and imported brands at competitive prices. Ask for Alaska or similar Filipino brands.
- Online (Shopee, Lazada). Wide selection with delivery. Prices range from P150 to P400 per 500-millilitre bottle.
- Garden centres. Stock premium brands with deodorised formulas for indoor use.
- DIY option. Make fish amino acid (FAA) at home by fermenting fish scraps with equal weight brown sugar for 3 to 4 weeks. Strain and dilute 15 millilitres per litre of water.
Frequently Asked Questions
What is fish emulsion fertilizer?
Fish emulsion is a liquid organic fertilizer made from processed fish byproducts. Manufacturers heat and liquefy whole fish or fish waste, then filter and stabilise the resulting liquid. The typical NPK ratio is 5-2-2, making it a nitrogen-rich fertilizer ideal for leafy growth. Fish emulsion also contains trace minerals, amino acids, and beneficial microorganisms that synthetic fertilizers lack. It works as both a soil drench and foliar spray for fast nutrient delivery.
How do I apply fish emulsion to plants?
Dilute fish emulsion according to the label, typically 15 to 30 millilitres per litre of water. Apply to moist soil around the base of plants every 2 weeks during the growing season. For foliar feeding, dilute to half strength and spray on leaves in the early morning. Avoid applying in direct midday sun to prevent leaf burn. Water plants lightly before application to protect roots from concentrated nutrients. The smell dissipates within a day after application.
Does fish emulsion fertilizer smell bad?
Yes, fish emulsion has a strong fishy odour during and immediately after application. The smell typically fades within 24 to 48 hours as the product soaks into the soil. Deodorised versions are available at a slightly higher price and reduce the smell significantly. To minimise odour, apply in the morning when temperatures are cooler and water thoroughly after application to wash the product into the soil. Avoid using fish emulsion on indoor plants unless you use a deodorised formula.
