We know fish has plenty of proteins and oils that are good for us, but is fish fertilizer good for our plants? Sometimes it’s hard to look beyond the marketing hype and figure out what counts when it comes to taking care of our gardens. 

Don’t get me wrong. I’m not down on fertilizers. Some plants are heavy feeders, and no matter how much you compost and take care of your soil, sometimes a little extra something is a big help. For that matter, indoor gardens just don’t have the same access to nutrients that your outdoor plants have, so fertilizer can be a huge help there, too.

When it comes down to it, though, is one fertilizer that much better than another? And is fish fertilizer all that different? And what benefits does it offer?

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Find out what fish fertilizer can offer your foliage and fruits

First, what exactly is fish fertilizer? It goes by a few different names. One company refers to it as “sea-based ingredients.” You’ll also see it listed as fish emulsion, fish hydrolysate, and fish meal. Fish meal is usually a dry product that you mix into your soil. Fish emulsion and fish hydrolysate are usually liquid concentrates that you mix with water.

Though the processes are different, both are made from the byproducts of the fishing industry. They can also be highly nutritious for plants. Interestingly, the NPK numbers (nitrogen, phosphorus, and potassium) are usually much lower for fish fertilizers than for many chemical-based fertilizers. While this may seem like a deficit, the reality is that the nutrients are released more slowly, meaning it’s a lot harder to overfeed your plants and burn them. 

Let’s get into the specifics, though. What are the benefits of fish fertilizer in comparison to other fertilizers or no fertilizer at all?

1. Fish fertilizer is usually acceptable for organic gardens since many of them only contain fish products.
2. The slow release of natural nutrients is good for your plants, but it’s also good for soil health. 
3. If you use a liquid fertilizer, one bottle of concentrate can go a long way, making it potentially a less expensive option.
4. Some brands of fish fertilizer may also contain nutrients such as calcium, magnesium, and sulfur.
5. You can use it as a foliar spray, meaning the plants can absorb the nutrients more directly through the leaves.
6. Some sources suggest that fish fertilizer helps plants produce more sugars, resulting in tastier vegetables. 
7. It’s non-toxic, so you don’t have to worry about harming bees, butterflies, and other beneficial insects.

In addition to your tomatoes and other garden vegetables, you can also use fish fertilizer on your other plants. Indoor and potted plants love it. People love it, too! (No, do NOT use this on your family! I’m talking about reviews here.)

I took a quick skim through Amazon, and every single fish fertilizer has either 4 1/2 or 5 stars. That’s out of hundreds and thousands of reviews. The lowest rating I saw was 4 stars, and I only saw one of those. To be fair, I did also look at “plant fertilizer,” and the reviews were similar. Maybe people just really like fertilizer?

I suppose the point is that, like so many things in gardening, there is more than one correct answer. However, if you are searching for fertilizer, and you’d like to improve your soil while you feed your plants, fish fertilizer seems to be the big winner here. Or, if you really want to take the DIY approach, you could make your own fertilizer. It’s fun. I promise!

Have you used fish fertilizer? What kind of results did you get?

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