How to Make Fish Emulsion Fertilizer at Home

Fish emulsion fertilizer, also known as liquid fish fertilizer, is an organic fertilizer made from whole fish or fishing industry byproducts like fish scraps, fish oil, and fish meal. Gardeners can buy commercial fish emulsion fertilizer or use their own homemade fish emulsion fertilizer mix to supply nutrients to plants. This type of plant fertilizer is used on houseplants and outdoor plants alike.

Consider some of the benefits of using fish emulsion fertilizer on your garden or lawn.

1. 1. Fish emulsion fertilizer is fast-acting. Compared to using compost, which acts as a slow-release system for plant nutrients, fish emulsion is a fast plant food that transfers nutrients quickly.
2. 2. Fish emulsion fertilizer is made from organic matter. Unlike synthetic chemical fertilizers, fish emulsion is environmentally friendly. This organic matter feeds microbes and stimulates the growth of microorganisms that improve soil health.
3. 3. Fish emulsion fertilizer is rich in nutrients. Most fish emulsion fertilizers have an NPK ratio around 4:1:1, meaning they are high in nitrogen (N) and lower in phosphorus (P) and potassium (K). Fish emulsion fertilizers often include other trace elements, or micronutrients, like calcium and magnesium.

Follow a few simple steps to make DIY liquid fertilizer.

1. 1. Gather the necessary materials. You will need canned fish or fish parts, sawdust, unsulfured molasses (molasses with no additives), water, a five-gallon bucket, a bucket lid with holes, and a screen to strain off insoluble parts.
2. 2. Combine the mixture. Fill the bucket halfway with equal parts fish and sawdust, add a cup of molasses, then add enough water to cover the ingredients. Mix the fish, sawdust, molasses, and water together until thoroughly combined. Seal the bucket with the lid with holes to allow airflow.
3. 3. Stir the mixture regularly. Use a paint stir stick or small shovel to stir the mixture every day for the next two weeks.
4. 4. Strain the mixture. Once your fertilizer mixture is done steeping, strain out any solids with the screen and save the liquid in another container.
5. 5. Reuse the leftover solids. After you’ve strained your fish emulsion fertilizer, you can reuse the scraps by adding more water and molasses to the bucket and restarting the process for another batch.

Use homemade or commercial fish emulsion fertilizers as an essential part of your plant care routine.

1. 1. Dilute your fertilizer concentrate. Always dilute store-bought fish emulsion fertilizer according to the directions on the container. To dilute homemade fish emulsion concentrate, add one tablespoon to one gallon of water before applying the fertilizer to plants.
2. 2. Fertilize your plants’ soil. Use a watering can to apply the diluted fish emulsion fertilizer to your garden or lawn as a soil drench. To encourage your plants to absorb the fertilizer, water the soil immediately after fertilizing.
3. 3. Spray your plants’ leaves with fertilizer. To use your fertilizer as a foliar spray, apply it directly onto the leaves of your plants with a spray bottle. You can also use a hose-end sprayer to apply your homemade fertilizer to your lawn.

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