Shrimp shells can be composted in regular backyard compost piles or bins. They are rich in Nitrogen, and should be considered a green material. Along with breaking down quickly, the materials that make up shrimp shells are also antifungal and help plants’ metabolisms in other ways. Credit:
However, we shouldn’t just use shrimp shells and tails. A compost pile can also break down lobster, crab, mussel, prawn, clam, and even oyster shells. Even if you don’t have a compost pile, bin, or tumbler,.
Although it may be surprising, Shrimp Shells and Tails, as well as all crustacean shells are fully biodegradable. They will decompose readily in an active compost pile, and are an excellent ingredient in any compost recipe. I’ve been using shrimp shells in my compost for years, and will share all that I’ve learned.
This is a quick and easy way to add them to an active compost pile: if you’re in a hurry, just throw them in the middle of the pile. Put them in the middle of the hot pile without washing or rinsing them. Their C:N ratio is very low, which means they will break down very quickly, which they do.
Even so, I thought some of you might be interested in the details of shrimp shells and how quickly they break down. So, I’m going to divide this article into smaller pieces because there is a lot of interesting information about how shrimp and crustacean shells break down.
As a seafood lover, you may find yourself with a surplus of shrimp tails after a summer barbecue or beach picnic. But before tossing those leftover shells in the trash, consider composting them instead. Shrimp tails can add beneficial nutrients to your compost. However, due to their high nitrogen content, strong odor, and potential to attract pests, composting shrimp tails requires some special handling.
In this article, we’ll cover everything you need to know about composting shrimp tails, including:
- The benefits of composting shrimp shells
- Potential problems with shrimp tails in compost
- How to prepare shrimp tails for composting
- Best practices for adding shells to your pile
- Alternatives like burying shells or curbside pickup
Follow these guidelines and you can safely compost shrimp tails without a stinky mess!
Why Compost Shrimp Tails?
While most animal products are discouraged from home compost piles shrimp shells offer several advantages
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Rich in nitrogen Shrimp shells contain chitin, a type of nitrogen-rich carbohydrate that provides nutrients for soil microbes. This extra dose of nitrogen helps accelerate the composting process.
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High calcium levels: The shells also contain calcium carbonate, a key nutrient for healthy plant growth and development. Calcium helps fortify cell walls and aids in new cell formation.
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Deters pests: As shells break down, they release chitin which can help deter parasitic nematodes in garden beds. The chitin feeds beneficial microorganisms that attack nematodes.
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Environmentally friendly: Composting reduces waste sent to landfills. Over 145 billion shrimp are produced globally each year. Composting the shells prevents this waste from burdening landfills or polluting oceans.
Potential Drawbacks of Composting Shrimp
However, composting shrimp shells also comes with some caveats:
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Strong odor: Decomposing shrimp emits a strong, fishy smell that can be unpleasant and attract pests. Taking steps to contain and bury odors is crucial.
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Pest magnet: Raccoons, rats, flies, and seagulls can all be drawn to the scent of rotting shrimp. An enclosed compost bin is a must to keep pests out.
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Risk of disease: Shellfish may contain bacteria or viruses that can survive composting. Always cook shells thoroughly before composting to eliminate risks.
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Slow to break down: Whole shells degrade slowly compared to other organic materials. Shells should be chopped or crushed before adding.
Prepping Shrimp Tails for Composting
To avoid issues with odor and pests, it’s important to properly prepare shrimp tails before adding them to your compost pile:
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Remove any meat, sauce, or seasoning: Shrimp meat will cause odors and should be discarded or composted separately. Rinse away any oil, spices, or breading on shells.
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Cook shells thoroughly: Boiling shells for 15-20 minutes sanitizes them and reduces odor. Bake shells at 200°F until dried and brittle.
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Crush shells into small pieces: Break shells down as much as possible, using a rolling pin or your hands. Smaller pieces mean faster composting.
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Mix crushed shells with carbon materials: Mix crushed shells with dried leaves, sawdust, wood chips, or shredded newspaper before composting.
Following these steps prepares shrimp shells for rapid decomposition with minimal smell or pest problems.
Best Practices for Composting Shrimp Tails
When adding prepped shrimp shells to your compost pile, follow these guidelines:
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Bury shells in the center: Place shells in a 6-12 inch deep hole in the hottest part of the pile. Cover them with 10-12 inches of other compost materials.
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Limit shell volume: Shells should make up no more than 10% of total compost volume. Too many may overwhelm and unbalance nutrients.
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Mix and turn pile frequently: Turning helps distribute shells and speed breakdown. Turn at least once per week.
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Moisten pile: Shells require moisture to decompose. Water pile as needed to maintain 40-60% moisture content.
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Use enclosed bins: Covered bins contain odors and prevents pests. Elevated bins further deter small animals.
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Avoid overloading bin: Add no more than 2-3 pounds of shells per cubic yard of compost. Overloading slows decomposition.
With the proper precautions, shrimp shells can safely enrich compost without issues.
Alternatives to Composting Shrimp at Home
If composting shrimp shells at home seems too risky or difficult, consider these alternatives:
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Curbside pickup: Some municipal compost programs accept seafood shells. Check with your local waste services.
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Drop-off composting: Many community gardens and urban farms have public compost bins accepting seafood waste.
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Burial: Bury shells 6-12 inches underground in garden beds for slow release of nutrients as they decompose.
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Vermicomposting: Adding small amounts of crushed shells to worm bins provides nutrients for the worms.
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Soil incorporation: Mix crushed shells into soil as a fertilizer. Works best for large-scale applications.
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Trash: As a last resort, shells can be thrown away after cooking thoroughly to remove odors and bacteria.
Frequently Asked Questions
Can you put whole shrimp in compost?
Whole shrimp including flesh and tail should be avoided as it’s more likely to cause odors and attract pests. Cook shells thoroughly then remove flesh before composting.
Do shrimp tails compost quickly?
No, shells take quite a long time to break down compared to other organic waste. Crushing shells speeds decomposition, but expect shells to take many months to fully compost.
What else can be composted from seafood?
Shells from lobster, crab, crawfish, clams, mussels, and oysters can all be composted using the same precautions as shrimp shells. Avoid composting fish bones or seafood meat.
Can shrimp shells go in worm compost?
Yes, in very small amounts. Crush the shells first, and limit to 1-2 spoonfuls per square foot of worm bin surface area. Monitor closely for any odor issues.
Are coffee grounds good with shrimp shells?
Yes, mixing crushed shells with nitrogen-rich coffee grounds can provide some odor camouflage and balance out the carbon-nitrogen ratio.
Can you put shrimp shells in garden soil?
Yes, burying crushed shells a few inches deep directly in garden beds is an easy way to get their nutrients into your soil without dealing with composting.
Composting shrimp tails is possible with careful preparation and management. While they require some extra consideration, the nutritional boost shells provide can be worth the effort for your compost and garden!
Chitin – what is it made of?
Chitin is a technical term for a group of molecules that make up about 15% to 40% of the shell of a shrimp, lobster, or other crustacean. Chitin is the reason Shrimp Shells are so excellent for composting. Basically, it is a combination of carbon, nitrogen, hydrogen and oxygen. The chemical formula for Chitin is C8H13O5N·H2O [2].
What can we learn about composting from that chemical formula? To put it simply, Chitin has an 8:1 C:N ratio. Meaning that Chitin is a very ‘green’ material. The C:N ratio of a perfectly balanced compost pile will be between 20 and 30 parts carbon to 1 part nitrogen. [3] That means that shrimp shells are an excellent source of nitrogen rich compost material. They will help your compost pile or bin get quite hot. Also, you need a hot compost pile to kill any weed seeds that might be hiding in it.
Are shrimp shells brown or green
Shrimp shells are a ‘green’ compost material, as their C:N ratio is 8. Any material with a C:N ratio less than 30 can be considered a ‘green’ material. [3][6].
As stated above, Shrimp or other crustacean shells are made up of between15%-40% chitin. And the chemical formula for Chitin is C8H13O5N·H2O. To determine if a material is ‘brown’ or ‘green’, we just need to determine it’s C:N ratio. Chitin has eight carbon atoms and one nitrogen atom in each molecule, so the C:N ratio is 8.