When you keep backyard chickens, you often have many eggshells. Have you ever wondered what to do with all those shells besides throwing them away? This post shares many different ways to use eggshells around your home.
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How to Compost Eggshells
The easiest way to keep from throwing your eggshells away is to compost them. Keep a bucket or container in your kitchen and place your eggshells in the bucket with other vegetable scraps.
Every couple of days, empty the bucket into your compost bin. For faster decomposition, you can crush the shells before adding them to the bucket.
The eggshells may not totally decompose, but as you’ll find out below, the pieces of shells that remain can help your garden in multiple ways.
Read How to Start a Backyard Compost Pile for more information.
Use Eggshells With Houseplants
You can use eggshells to help your houseplants grow bigger and better. The shells serve two purposes.
One, they can add nutrients and minerals to the soil to help your houseplants grow better.
Secondly, if you mix eggshells into the soil, it can help keep the soil from compacting into the container. Over time, as you water plants from the top, the soil in container-grown plants becomes more compact.
Even if you water from the bottom, the soil in your houseplant containers will settle after a while. The eggshells will help to keep the soil looser and easier for the roots to grow through.
Add Eggshells to Tomato Plants
Tomato plants need a steady supply of calcium in order to prevent some diseases. Adding crushed eggshells to your tomato planting hole in your garden can help provide them with the calcium they need.
The shells take a while to break down so they provide a steady supply of calcium instead of a bunch all at once.
You can also top-dress your tomato plants with eggshells too. And because the shells break down slowly, you are unlikely to “overdose” your plants on calcium by using eggshells.
Adding eggshells to the planting hole when transplanting tomatoes outdoors can definitely help your tomato plants, especially if they are prone to blossom end rot.
Use Eggshells to Keep Slugs Away
Another use for crushed eggshells in the garden is to keep slugs from eating your tender vegetables. Slugs don’t like crawling over sharp objects and crushed eggshells are definitely sharp.
Sprinkling crushed eggshells among your garden plants can help prevent slugs from reaching the plants. I especially like to sprinkle them throughout my strawberry bed to prevent the slugs from ruining my harvest.
To Keep Cats Away
While I haven’t tried this myself, I have heard that you can use eggshells to keep cats away. If you have trouble with neighborhood cats doing their business in your garden or flower beds, this is definitely worth a try.
Supposedly, the cats don’t like walking on rough surfaces so the eggshells will keep them from walking in your garden.
(Unfortunately, cats like doing their business in nice soft soil, and your garden is the perfect environment for them. However, they can quickly ruin vegetables as it is unsanitary for them to defecate among food you plan to eat.)
Eggshells shouldn’t harm your plants or flowers so you don’t have much to lose if cats are a problem in your yard. I would leave the shells in larger pieces and sprinkle them liberally among your fruit and vegetable plants.
Feed Eggshells Back to Your Chickens
An eggshell is made up of 40-50% calcium carbonate. So as your flock lays eggs, it depletes their body of calcium if they aren’t taking in enough.
You can feed your eggshells back to your chickens to increase their calcium intake and to ensure thick, strong eggshells.
You can use the shells to replace purchased oyster shell or to supplement it and keep costs down. It will depend on how much additional calcium your flock needs. (I like to use both.)
I highly recommend crushing the shells into small pieces before giving them to your flock. Otherwise, your chickens could develop an egg-eating habit.
And when feeding your chickens the eggshells, offer them in a separate container, not mixed in with their food. This allows your hens to take what they need without consuming too much calcium. (And if you have roosters, they don’t need the extra calcium anyway.)
Some people prefer to sterilize their eggshells before feeding them back to their flock. This is totally up to you.
As long as the eggshells came from my hens, I don’t mind feeding them back to them without the sterilization process. I feel that my chickens have a natural immunity to any diseases the shells might contain.
However, if I was feeding them eggs from the store or another flock I would sterilize them first.
How To Sterilize Eggshells
Rinse the shells well and place them on a baking sheet. Bake at 250 degrees for 20 minutes. Allow the shells to cool. They should crush very easily.
Feed to Wild Birds
Just like chickens need calcium, so do wild birds. Before you feed the shells to wild birds, you do need to sterilize as they could pick up diseases from the shells. You can sterilize them the same way I described above.
Once dry and cool, crush the shells and add them to a bird feeder or sprinkle them on the ground where the birds tend to hang out. Try to crush them pretty small since most songbirds don’t have large beaks.
Use as a Calcium Supplement
While using eggshells as a calcium supplement is a bit controversial, I did want to mention it here. You can save your shells, boil them, bake them, and then grind them to a powder to use internally.
You can find out more information on using eggshells as a calcium supplement here.
What I Don’t Recommend
Time and time again I keep seeing people suggest using eggshells to start seedlings. While seems great in theory, there are several problems with this idea.
First, you really need to be able to poke a hole in the bottom of the eggshell to allow for water drainage. Otherwise, the seedlings can rot.
Secondly, you must use plastic or styrofoam egg cartons to hold the half-shells. If you don’t use egg cartons, the shells won’t sit upright.
And you can’t use cardboard egg cartons because the water will just seep right on through.
Finally, half an egg shell is really not deep enough to provide a good root structure for most plants. You can probably get the seeds to germinate in the eggshell but they would need to be transplanted within a week.
You’ll save less time in the long run by starting your seeds in deeper pots or something designed specifically for seed starting.
How Do You Use Eggshells?
Do you have other ways you use eggshells? If so, I would love for you to leave a comment telling me the ways you use egg shells around your home and garden. I would love to update the post with even more ideas.