Does Fish Emulsion Fertilizer Attract Pests?

Fish emulsion fertilizer is an excellent option if you want an organic way to add nitrogen-rich fertilizer to your soil. However, there are a few drawbacks to choosing this sort of fertilizer, like the smell. So that begs the question: Will fish emulsion attract unwanted pests into your garden? 

Fish emulsion fertilizer does attract pests. Any critter that enjoys the smell of rotten fish like rodents, cats, flies, and snakes will be far more likely to visit your garden when you use fish emulsion fertilizer. However, the smelly effects of this fertilizer wear off pretty quickly. 

In the rest of this article, I’ll go over what fish emulsion fertilizer is, how long the scent lasts, how you can make it, and why it attracts some pests and repels others. So if you would like to learn more about using fish emulsion fertilizer and how pests will react to it, be sure to keep reading. 

What Is Fish Emulsion Fertilizer?

First, it’s essential to understand precisely what fish emulsion fertilizer is. If you guessed that it’s a fertilizer made of fish, you’d be correct. However, people still love to use this rotten fish mix in their gardens for several reasons. So what exactly is in emulsion fertilizer? 

Fish emulsion fertilizer is an organic fertilizer made from fermented fish. This fertilizer is excellent because it has a lot of natural nitrogen and is great at slowly releasing nutrients into the soil. Plus, it can easily be made at home. But, unfortunately, it’s pretty smelly. 

When making homemade fish emulsion fertilizer, the mixture generally contains fish, sawdust, water, and molasses. However, it can take 2-3 weeks for the fish to be completely fermented and ready for use. So if you make your own, you’ll have to be patient. 

What Pests Does Fish Emulsion Fertilizer Attract?

Now that you understand what fish emulsion is and all of its ingredients, it’s time to talk about its effect on pests in the garden. But, first, you are probably wondering which pests this fish fertilizer will attract (because you don’t want to have to deal with those, after all!). 

Fish emulsion fertilizer attracts pests like rodents, cats, snakes, flies, and other meat-eating critters. However, the strong scent of fish does not last long, and you should only be bothered by these creatures for a short time, if at all. Unfortunately, though, some pests may dig in the soil. 

Basically, any critter that enjoys meat may take a walk through your garden beds to see if they can sniff out the source. Some animals may even dig a little in your soil to see if they can locate the source of the fishy smell. Mice especially are attracted to this fertilizer. Luckily, the smell doesn’t last more than a few days, so the pests should leave your garden space after that. 

However, if you often use fish emulsion fertilizer on your plants, it may be a good idea to invest in a defense system for your garden. I recommend a motion-activated sprinkler. It is excellent because it auto-senses movement and sprays animals bothering your plants. Plus, it can be set to only work during the day or night, so you don’t have to worry about being unpleasantly surprised by a spray of water at the worst time. 

Does Fish Emulsion Repel Some Animals?

Now you know that this smelly fertilizer can attract unwanted attention from certain pests like mice, skunks, and even coyotes. But can it also repel certain animals? If so, which animals dislike the fishy scent of this fertilizer? 

Fish emulsion does repel some animals. Due to the rotten fish smell, herbivores will be far less likely to enter your garden. So animals like deer, moose, and rabbits are likely to steer clear of your garden until the smell has dissipated. This is a benefit, as these animals can destroy gardens. 

So as you can see, fish emulsion can keep some garden pests out. Rabbits and deer are especially known for chowing down on unattended foliage. So a tiny reprieve from their presence can be a good thing, so long as you can handle the fishy smell perfuming your garden. 

What Pests Does Fish Emulsion Fertilizer Repel?

Next, I want to talk in greater detail about what pests fish emulsion fertilizer actually repels. Of course, you know that it can help keep out rabbits and deer. But are there any other critters that don’t enjoy the fishy fertilizer? 

Fish emulsion will repel pests like deer, rabbits, mites, caterpillars, and nematodes. This fertilizer is more commonly used to keep gardens healthy but can also be used as a natural pest deterrent. However, the effects only last a short while as the strong scent dissipates. 

This emulsion will not only clear out rabbits and deer for a short time but also help deter some buggy garden pests. Caterpillars especially love too much on plant leaves, and anything that’ll deter them from calling your plants home is a good thing. 

How Long Does the Smell of Fish Emulsion Last?

Finally, it’s time to talk about the overwhelming smell of fish emulsion. It’s no secret that this stuff stinks. Fish emulsion smell is intense — both humans and animals notice it. So, how long will you have to put up with the putrid scent? 

The smell of fish emulsion will last about 1-2 days depending on how concentrated the emulsion was applied. Typically you mix fish emulsion with water to dilute it, and this reduces the potent fishy smell. You can add extra water to further dilute the mixture and ensure the smell wears off sooner. 

You can make your emulsion more watery if you want a less powerful scent. However, a more concentrated dose can be beneficial for your plants, and you only have to briefly put up with the foul odor. However, you should do your best to follow the application instructions listed on your bottle or the recipe you’re following. 

How To Make Your Own Fish Emulsion Fertilizer

Finally, I’d like to discuss how you can make your own fish emulsion fertilizer. Now, this stuff can certainly be purchased at the store if you aren’t up for making it. However, it’s actually quite simple and cheap to make from scratch. So let’s get started. 

You’ll need: 

  • Fish (it can be canned or even just guts)
  • Sawdust
  • Molasses
  • A container that seals

How to make homemade fish emulsion fertilizer:

  1. Blend up your fish parts in a blender until they’re liquified. 
  2. Place equal amounts of fish and sawdust into your container and one cup of unsulfured molasses. 
  3. Fill the container with water until all of the ingredients have been submerged. 
  4. Combine all the ingredients until the mixture begins to resemble a bad smoothie. 
  5. Place the lid on securely, and remember to stir the mixture daily for 2-3 weeks. 

Once the fish has had time to ferment fully, it’s ready for use. You can use this fertilizer as is with a bit of water or go one step further and drain out all the solids. This will result in a better liquid that can be applied directly to your plants. Of course, you can always reuse the strained fish bits for your next batch of fertilizer. 

For more details on how to make homemade fish fertilizer, you can read my other article here: How to Make Homemade Fish Fertilizer (DIY Guide)

As you can see, the overall process is quite simple and cheap. However, handling stinky fish is not everyone’s cup of tea, so many gardeners still opt to purchase this emulsion rather than making it.

If you want to learn how to make another type of fish emulsion fertilizer, you should definitely check out Garden Like a Viking’s YouTube video:


Ultimately, fish emulsion fertilizer attracts pests, which makes sense because if you were to leave out rotten meat, you’d get the attention of common garden pests like mice, skunks, and possibly raccoons. This is because the scent of rotten fish is appealing to them, and they will venture into your garden to locate the source of the smell. However, this fertilizer also does an excellent job of repelling certain pests like rabbits, deer, and caterpillars. 

Alexander Picot

Alexander Picot is the principal creator of, a website dedicated to gardening tips. Inspired by his mother’s love of gardening, Alex has a passion for taking care of plants and turning backyards into feel-good places and loves to share his experience with the rest of the world.

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