Gardening

Why burying dead fish is the secret to healthy citrus trees

Fish fertiliser is the way to go!

Why would burying fish under your plants be a good idea? 

As summer comes around and everyone starts to dig into fresh fish for dinner, stop and think before throwing away all the fish remains. It may come as a surprise to many, but fish are actually great fertilisers for your plants. 

Let’s take a look at the how and why of fish fertilising, but be warned, it is a bit of an icky process!

Tradition as old as time

Burying fish under plants as a source of nutrients is actually a tradition that goes very far back in time. 

The Three Sisters Method is a Native American way of growing plants in a symbiotic relationship. While it focuses on planting corn, pole beans and squash close together in a form of ‘companion planting’, it also involves planting fish under the plants to create nutrient rich soil. 

What does burying fish do for your plants?

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(Credit: Getty)

Burying fish remains under your plants provides excellent nutrients for them to grow happy, healthy and sometimes even bigger than usual! 

As the fish slowly breaks down and decomposes, it releases three essential nutrients for plant growth: nitrogen, phosphorus and potassium. And if you’re using a whole fish, you will also get trace minerals of calcium, magnesium and other great sources of nourishment. 

The great thing about burying a fish deep into the ground is that the nutrients and minerals released actually deposit within the soil and roots, not just on top of the plants. This means it can be more effective than a normal synthetic fertiliser. 

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(Credit: Getty)

Which plants does fish fertiliser work best for?

Fish fertiliser actually works amazingly well for citrus and other fruit trees! While lots of vegetable plants are smaller and do not require as much nourishment, citrus trees need lots of nutrients and minerals in their soil.

Burying a dead fish under your lemon tree will mean that the soil will absorb all the great nutrients and pass it through the root system, giving you a healthy and happy tree!

The plants that also have the deepest roots perform great with buried dead fish.

Of course, the temperamental tomato plant is one of the top contenders for fish fertiliser! Because of how fickle a tomato plant is with growing and being prone to disease, fish fertiliser will make it a healthy, strong and lush plant!

This is mainly because tomato plants have very deep set roots, which buried fish remains can easily reach to nourish properly. 

Is fish fertiliser better than synthetic fertiliser?

Fish fertiliser is not necessarily better than synthetic fertiliser, but it can be more effective. This is because the fish is buried and can create nutrient rich soil, which in turn nourishes the roots of plants very easily. 

When using normal spray or bottle fertilisers, you usually have to use it in large amounts to be able to reach the roots, and it can run the risk of causing fertiliser burn. Plus, fish fertiliser is a great way to get rid of any smelly fish remains you have after cooking!

How to bury fish under plants 

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(Credit: Getty)

The main consideration when burying fish is deepness. Because fish and decomposing fish are naturally quite odorous, many animals and insects will want to have a taste of it. The best way to avoid this is by burying your fish remains quite deep under your plants or installing a small chicken wire fence around the perimeter of your garden. 

The easiest way to bury fish remains is just by leaving them whole and digging a hole under your plants. Be careful not to disturb or damage your plant’s root system when creating your hole. 

The other two ways to bury fish are through ‘fish fertiliser’ or composting:

Fish fertiliser 

Creating fish fertiliser can be a bit of a gross process, but it is definitely worthwhile in the end. Instead of leaving your fish remains intact, use a stick blender or hand grinder to grind up the different parts of your fish. This will create more of a paste that can easily be spread across larger gardens if necessary. 

For this, we do not recommend using a blender that you already use in the kitchen and instead have a separate stick blender for gardening purposes. 

Fish composting 

Fish composting is definitely the more palatable way to incorporate all those nutrients into your garden. Rather than burying your fish fertiliser, placing it in your compost to decompose and then use in your soil is a great option. This process may take a little longer, and does require composting tools. 

A further warning of animal attraction is attached to this method as well, as many animals can easily be attracted to the rotting smells of composting. 

Where to source fish heads and scraps 

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Scraps you will want to include in your fish fertiliser: intestines, liver, gallbladder, heart, fins, tail, scales, fish head and gills and all the bones. 

Finding fish remains can be as simple as buying a whole fish for dinner. When buying from the fishmonger, it will most likely be scaled and gutted, but you can ask for the remains to be placed in a separate bag. 

Alternatively, if you do not eat whole fish all that often, you can ask your local fishmonger or fish market for fish scraps. Because these remains are not wanted often, they usually will give them out for free. 

Finally, you could go for the trickiest option and fish for your fertiliser yourself!

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