Can You Compost Shrimp Shells?

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If you love seafood, you may wonder if you can compost shrimp shells.

The answer is yes, but there are some guidelines you need to follow when composting shells from shrimp.

Once you learn the tricks to composting the shells from shrimp successfully in this guide, you’ll never worry about what to do with all the scraps after enjoying a delicious shrimp dinner!

Can Shrimp Shells Go In Compost?

Shrimp shells, along with any other type of shells from crustaceans such as lobster or crab, can go into compost either raw or cooked. 

Many people hear that you shouldn’t put fish or shellfish meat into compost, which is valid to an extent, and then also assume that the shells should not be an ingredient.

Luckily, shells and peels that are clean from large chunks of shrimp meat are okay to compost either directly into the soil or as a “green” or nitrogen-based ingredient into your composter or pile.

The shells of shrimp are useful when composting, as both a lightweight aeration agent and for their minerals that add nutrients to the compost. The peels also contain certain compounds that fungi and bacteria thrive on, which enhances the breakdown of the compost materials.

You can safely compost shells from shrimp in both hot and cold composting systems but will experience faster results when composting hot

Pros And Cons Of Composting Shrimp Shells

There are benefits to composting shrimp peelings but also some negatives you may wish to consider before incorporating them into your compost pile or tumbler. 

Pros:

  • The shells contain a compound known as chitin, which is beneficial to plant health for its ability to enhance disease resistance
  • Chitin also feeds good fungi and bacteria within the compost so all the material breaks down quicker
  • The shells provide a high source of nitrogen to the finished compost, which plants need to grow strong
  • Provides a great way to recycle kitchen scraps and reduce landfill waste
  • Calcium carbonate is another mineral in the shells that can help raise pH levels in compost (or soil) that is too acidic

Cons:

  • The odor can attract pests to your compost bin or pile if you don’t bury it properly
  • The shells break down better with extra effort, such as drying and crushing which many people may find too time-consuming 

How Long Does It Take For Shrimp Shells To Decompose?

Expect full decomposition of shrimp peelings to take as little as a few months on up to a year or more. 

How you treat the shells before adding them to your compost, plus the type of compost system you use will have a significant impact on how much time they take to decompose.

For the quickest action, allow your shrimp peelings to dry out before crushing them up and adding them into a hot compost system. Following this method will reduce the shells down within three to four months.

If you toss whole raw shells into a cold compost system that you neglect most of the time, it could take at least a year to see them break down and become unrecognizable.

Composting Tip: After a shrimp dinner, I like to collect all the shell scraps on a wide baking sheet and pop them into the oven until they are crispy. I then shove them into my food processor and grind them up into small bits. 

Once I add this to my compost, they are well on their way to “disappearing” within a few months. Another bonus is that cooking the shells and heads reduces the odor and the chance you’ll have unwanted visitors to your composter.

How To Compost Shrimp Shells

Step 1. Collect the shells from shrimp and decide how you would like to deal with them.

You can choose to either:

  • A. Dry out the shells by baking them in the oven or leaving them out to air dry before adding them, as is, to your compost.
  • B. Dry out, then crush the shells down into smaller pieces before adding them to your composter.
  • C. Leave shells, either cooked or raw, wet, and add them directly into your compost. You could use a pair of kitchen shears to cut the pieces down easier.

TIP: If you want the benefits shrimp peelings can add to your finished compost but don’t care to buy and eat shrimp, you can always ask friends or local seafood restaurants for any scraps.

Step 2. Dig a hole into the center of your existing compost and add in the shells. 

Step 3. Cover the shells with more compost material. Add in other brown ingredients if you feel the ratio is out of balance, and also mist with some water if the compost feels dry.

Pests can really sniff out the shells, especially if you add them wet, so the better you bury them within the pile, the better.

Step 4. Turn the compost every three to seven days until complete. If you compost in an outdoor pile, a garden fork is very efficient for turning and aerating the pile at the same time.

Can you vermicompost shrimp peelings?

For those of us that utilize a vermicomposting system along with traditional composting methods, the good news is that I find the worms love shrimp peelings and have no issues digesting the material.

While I know many who toss in whole shells and ignore the smell that emanates for a few days, I prefer to dry them and crush them up into as fine a texture as possible.

Worms can use this material for nutrients, but also as grit, to help them digest all the food inside the vermicomposter.

In Summary

Gardeners with experience know using compost made with shellfish scraps provides even more nutrients and disease-preventing benefits to plants. Reducing household waste and recycling those bothersome shrimp shells into rich compost is a win-win for both you and your garden.

By following the steps in this guide, lush shrubs, bountiful flowers, and generous vegetable harvests can be yours this next growing season!