How To Prepare And Use Eggshells In The Garden

Native Americans had a rule: When you hunt, you use every part, so nothing is wasted.

Today, we tend to waste so much that it could easily be used, and massive landfills could take centuries to degrade. Even worse, when you buy many products at the store, you end up with a large portion of those products being discarded.

eggshells in the gardenPin

But this doesn’t have to be the case, and we’re going to show you how to use one of the most important pieces of kitchen scrap out there: egg shells.

Eggshells are a powerhouse of benefits for your garden when used right.

Let’s look at how you can turn those egg shells into garden gold.

How To Prepare And Use Eggshells In The Garden

Eggshells are an amazing addition to your garden routine, although they need some preparation before you can use them.

Why Use Eggshells?

It’s one thing to say that eggshells are good for the garden bed, but another to actually know why.

Here are just some of the wonderful qualities of eggshells.


Eggshells are organic materials that are chock full of calcium carbonate, the most easily processed form of calcium. This makes them a great addition to your outdoor compost pile, where they will be broken down and enhance the necessary elements, like the calcium content available.

In fact, approximately 94% percent of the shell is pure calcium carbonate. This makes egg shells a great calcium supplement for your plants and garden soil, as they help the plant roots absorb the essential nutrients easily.

Additionally, there’s approximately 3% percent each of phosphorus and magnesium, two other valuable nutrients.

Beyond these are traces of copper, iron, manganese, potassium, sodium, and zinc.


Crushed eggshells may or may not help in repelling snails and slugs.

This is a popular use for eggshells, but there is no conclusive evidence that the shells do or do not work, so your own mileage may vary.

The calcium in egg shells can also help protect against several diseases, most notably blossom end rot, which more commonly attacks plants suffering from calcium deficiency.


Agriculture lime (or aglime) is an important tool for reducing soil acidity and adding a source of calcium to your soil.

But aglime can be expensive, and the process of mining it can be very destructive.

Now, what if we told you that egg shells do exactly the same thing as aglime but won’t cost you anything (if you already buy eggs, that is)? 

Whether you’re working on a tight budget or concerned about the effects of quarrying, using eggshells in place of agriculture lime to keep acidity levels low makes sense. You can definitely use eggshells as an excellent alternative to amending your lawn with lime. 

The Trouble with Eggshells

Before we go further, it’s important to point out that you can’t simply toss your eggshells into the garden and expect great things.

If you’re growing blueberries or other acid-loving plants, the eggshells can be counterproductive, as they’ll raise the pH level of your soil slightly more towards neutral.

Additionally, the pieces can take a long time to break down if not properly prepared, meaning you won’t see those benefits for some time.

Thankfully, it’s easy to prepare eggshells for garden use, and several ways exist.

Ways To Prepare Eggshells for Garden Use

Before preparing your eggshells, you must determine how you wish to use them.

For compost piles or pest control, you will want crushed or ground eggshells.

For a soil amendment, you’ll need pulverized eggshells. But for egg shell tea, you can use intact eggshells.

Let’s loot ways to do each.

Sterilizing Your Eggshells

Most people prefer to simply rinse the leftover eggshells out with hot, soapy water and place them on a paper towel to dry. Make sure to remove any raw egg to avoid unpleasant smells and avoid attracting flies.

Once rinsed, the dry eggshells won’t stink or attract pests and are generally ready to go.

However, if you’re worried about salmonella bacteria, you can pop them in the oven or microwave for a few minutes to dry and kill them. This process of exposing the eggshells to temperatures is called the oven-drying method.

Eggshell Tea Prep

Since we’re talking about tea, let’s begin with this method.

Eggshell tea is a liquid amendment used when watering or fertilizing your plants. The egg shells can be discarded or reused later for other methods in this method.

Bring a gallon of water to a boil and add the shells of 10 to 20 eggs.

The more you add, the stronger the tea will be.

Allow it to boil for 20 minutes or so, then take off the heat and allow it to steep for 24 hours.

Once done, strain out the solids and put your eggshell tea in a jar or other sealable container until you’re ready to use it.

Eggshell Compost and Slug Control Prep

You can technically use intact eggshells for composting, but it’s better to break them down a bit, especially if you compost using vermiculture.

To do this, simply use a mortar and pestle, coffee grinder, or kitchen blender to crush the eggshell into small pieces.

If for some reason, you don’t have a mortar and pestle, you can use a food processor or place the shells in a Ziploc bag and crush them with a rolling pin.

Eggshell Fertilizer Prep

For the shells to properly bond with the soil and be the most useful, they must be completely pulverized into dust using a coffee grinder or blender.

This will take the most work, so you may wish to use a food processor. However, a mortar, pestle, or kitchen blender will also work if you’re patient. Don’t forget to put the finely ground eggshells in a jar for storage.

You can also mix the ground eggshells with garden soil as organic fertilizer while neutralizing acidity.

Using Eggshells in the Garden

Once the eggshells are properly prepared, you can put them to use.

We’ve included the previously mentioned uses here and a couple of additional ones to consider.

Bird Nutrition

Scientists spent a decade studying how birds can recover from brain damage and discovered it was actually the eggshells.

You can add crushed eggshells to bird feeders to give visiting birds an extra boost.

They also work well in chicken feed as a dietary supplement.


Add your eggshells directly into the compost heap or crushed shells to your worm box.

Worms actually need the grit to help them process foods, and the eggshell is a popular choice for hungry worms.

This also helps further break down the shells so microorganisms can easily finish the job.


While low in NPK, pulverized eggshell is recognized as a type of organic fertilizer.

To use, blend it in with your soil before planting or sprinkle a bit on top.

Before using, however, it;’s a good idea to test the soil to see if there’s a need for the extra calcium as well as to ensure you don’t raise the pH beyond the levels your plants will require.


It can take a while to collect enough eggshells, but if you’re patient (or know a restaurant willing to give you theirs), crushed eggshells can make a decent mulch.

The tiny pieces add color to the garden, especially if you have some brown eggs in the mix.

On top of that, they help keep the soil from drying out and will slowly degrade the soil. It can also help retain soil moisture and suppress weeds if you cover an entire garden with eggshells.

Pest and Disease Control

Sprinkle some crushed eggshells around vulnerable plants to provide a pest deterrent against snails and different species of slugs.

Remember, this is a controversial remedy, so it may or may not work for you.

Also, while there’s evidence that the smell of eggshells can help deter deer (to a small degree), they can attract mice and rats.

If you intend to use it for this purpose, we suggest first adding diatomaceous earth around the plants, then sprinkling a sparse layer of eggshell powder on top.

Diatomaceous earth is highly effective, and the shells will (at worst) help keep the DE from blowing away during a strong wind.

On their own, the crushed shells may also help attract worms as this material is an excellent source of grit or what worms need to digest their food. Once the worms are attracted, they will aerate the soil, but your mileage will vary.

In addition, adding eggshells together with Epsom salt which tomatoes love along with other organic matter into the planting holes also helps reduce the risk of blossom end rot by balancing the soil calcium levels.


Eggshell tea is an excellent, readily-absorbed calcium source for your seedlings and indoor plants.

Simply use it instead of plain water once every 2 to 4 waterings to give your plants a quick calcium boost.

A Final Note On Eggshell Starters

It’s been a popular trick to use eggshells as seed starters, and while this is possible, it’s not always the best idea.

While you can certainly use them for this purpose, we don’t recommend them.

Remember that eggshell break down slowly, so you can’t just plop the shell into the ground and expect the seedling to break out easily.

There’s a good chance the plant will become slightly rootbound before gaining enough strength to break through the shell.

Thus, if you intend to use eggshells as starters, giving the sides a tap to crack them before putting them into the ground is a good idea.

For most plants, however, eggshells will look pretty but require you to transplant the seedling to a peat pot or larger container before it’s ready to plant. However, you can also use your saved egg carton to hold your seeds until they’re ready for planting.

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