Last Updated on February 14, 2022 by Grow with Bovees
One of the big questions many avid gardeners ask is can you compost bones? The short answer is yes – bones are a type of food waste that is compostable, and can be added to your compost pile.
However, the process to compost bones is a bit different than let’s say wood, where whole carcasses and large animal bones must be cut into smaller pieces before adding them to your compost tumbler.
Read on to find out the best way to compost chicken bones and other types of bones, the best bones to add to your compost system, and how long it will take to decompose.
Should You Compost Bones?
Generally speaking, you want to steer clear of composting bones or any meat and animal products and by-products, or chicken and fish bones because they can cause problems if done incorrectly.
There are however certain composting systems such as Bokashi that allow you to compost bones. The Bokashi composting system works a bit differently than traditional composting systems, in that it uses beneficial microbes or living microscopic cellular organisms rather than heating and soil matter to break down plant matter over time.
When you add bones to your compost systems, they attract pests and can harbor pathogens such as E Coli bacteria if your pile doesn’t get hot enough.
What Bones Can You Compost?
In terms of the type of bones you can compost, you can add pork, chicken, beef and wild game, fish, and fish scraps.
Some of these types of bones decompose faster than others, so you can make and add compost quicker to your soil.
Can You Compost Chicken Bones?
Chicken bones are typically slimmer than most other types of bones, therefore composting chicken bones is quicker. However, it’s important to only compost cooked chicken bones to prevent harmful bacteria contamination in your compost bin.
Chicken bones are also rich in calcium phosphate and collagen fibers, so they help add calcium to your garden and plants.
Pig bones are thicker than chicken bones, so will take longer to break down. However, the softer parts of the bone such as the marrow and any remnants of meat will decompose much faster than bone.
Beef and Wild Game
Bones of wildgame like elk and deer are large and thick, so take longer to dissolve into your compost system.
If you don’t have time for pre-processing bones and breaking them up into smaller pieces of bones with bone scissors, or just don’t want to wait a while for them to turn into compost, your best option is not to include wildgame bones in your compost pile.
Can You Compost Fish Bones?
Fish bones are perhaps the thinnest bones of them all, hence are the easiest to compost. But fish and its bones do have a nasty odor, which you can get rid of by allowing the fish scraps to dry out before adding them to your compost pile.
How to Safely Compost Bones?
The safest way to compost bones is with a Bokashi bucket. Bokashi meaning fermented organic matter in Japanese uses a special inoculated bran to ferment your food waste.
It allows you to compost many types of food waste including animal bones, fish bones, raw bones, chicken wing bones, rib bones, and any other leftover bones.
Bokashi bone composting is also faster than traditional composting, and is a good choice for apartment dwellers looking to compost food matter.
Guide to Bokashi Compost System
You can make your own Bokashi compost system with Bokashi bins, a Bokashi mix, kitchen scraps, and a container, or you can buy a ready-to-use complete Bokashi system for a smooth and speedy composting process.
1. Add a layer of Bokashi bran to the bottom of the bucket, and then up to two inches of food scraps. Food waste can include plant food, meat bones, softer food, waste bones, leftover fish bones, uncut beef bones, turkey bones, unprocessed bones, and other types of bone scraps.
There are a few items you should not put in the Bokashi bucket including wax paper, aluminum foil, plastic silverware, and plates, etc.
Additionally, you should also break up larger bones and pieces of scraps into smaller pieces using a pair of bone-cutting shears or a similar tool.
Furthermore, puncture smaller whole items such as grapes or small potatoes, so that the composting microbes can find a way to get out and work.
2. Cover the scraps in the bucket with Bokashi bran, but be sure not to add too much as this may delay the decomposition process.
One way to tell if you’re adding too much bran is by smelling the bran-if there is no smell or a faint vinegar smell, then you’re fine, but if it smells bad, add more bran.
3. Next, use a plate lid or mid lid to press down and release the air, and leave it on top until you’re ready to add more food material.
4. Close the Bokashi bucket tightly, and repeat the steps until the bucket is full.
5. Remember, Bokashi is a two-bucket system, so you will probably find the bottom of the second bucket filled with liquid depending on the type of food you put in the bucket and the Bokashi mix.
This liquid is often referred to as Bokashi tea or Bokashi juice, and no you can’t drink it (pun intended), but you can pour the liquid down your drain or dilute it and use it as an extremely potent fertilizer for your plants.
Regardless of how long it takes to fill your Bokashi bucket, give it roughly two weeks for the fermentation process to complete, which under the right acidic conditions is the approximate time to break down the food.
After the fermentation process is complete, place a bucket with large holes partway into the ground, put the contents of the Bokashi bucket with alternating layers of soil in it, cover it with a lid tightly, and wait two to three weeks for the composting microbes to do their job of making compost.
2. Hot Composting
There are ideally two common ways of making compost-hot composting and cold composting. To briefly explain the difference between the two, a hot compost pile requires nitrogen-rich materials for the pile to heat up, whereas a cold compost pile requires minimal effort, but does take a year or two before it produces compost.
The heat generated in the hot compost pile works with the bacteria to reduce odor and speed up the breakdown of bone material. Cold composting isn’t a good option for bones, because animals can easily smell them, and dig out and eat them.
If you don’t have the ingredients to add to a hot compost pile such as shredded paper, dried corn stalks, grass clippings, citrus fruits and vegetable waste, coffee grounds and filters, and tea bags, you can dig a hole at least two feet deep, bury the bone scraps, and lay a piece of wire mesh over the hole.
Be sure to place a large rock over the mesh to hold it in place to deter animals from digging while the bones decompose naturally.
3. Break the Bones
Apart from breaking the bones, you can also grind the bones in a mortar and pestle for faster bone decomposition.
Some people boil the bones first and then burn them into charcoal before grinding them in the mortar and pestle. Ground bones will turn into compost much faster than smaller pieces of leftover fish bones, fresh chicken bones, or any other fresh bones.
How Long Do Bones Take to Compost?
The amount of time it takes bone joints and bones to compost depends on several factors, most notably the way you prepare the bones before adding them to the compost pile.
Bones are a mixture of calcium phosphate and collagen fibers, which are a treat to the bacteria and fungus that are growing in the compost bin.
Simply burning the bones in the ground is going to take a lot longer than adding bones to a hot compost pile. The time it takes to make bone compost can even take months for fish bones or other types of bones depending on the weather conditions.
Adding to this, it’s a good idea to place the entire bone, ground bone, or cooked bones in the center of the hot compost pile, and regularly turn the pile.
Are Bones Good for the Soil?
Bones may take longer to turn into compost, but are extremely healthy for all types of soils including sandy and peaty soils.
If you don’t want to make bone compost, you can even boil them in a pot for 15 minutes, remove the meat or fat still attached to them, or burn the bones and crush them.
Next, dry the bones in the sun for a few days, but keep them away from animals. After the bones are dry, crush them into a fine powder, and sprinkle directly over the soil as fertilizer or add to your compost pile.
Bone meal fertilizer is basically a slow-release fertilizer that will slowly release the nutrients for plant intake throughout the growing season. One of the biggest benefits of slow-release fertilizer is it prevents root burn and increases soil vitality.
Getting back to the big question — can you compost bones? The answer is “yes” as long as you do it the right way. It’s best to boil bones rather than adding raw bones directly to the compost pile.
Further, bones are solid, some harder than others, so it’s a good idea to chop them up into smaller pieces or better yet grind them to accelerate the compost-making process. You can even sprinkle the ground bone directly over the plants to serve as a slow-release plant fertilizer.