Eggshells And Gardening 🥚 What You Need To Know

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If your family eats eggs, you are probably in the habit of tossing the shells in the trash and might not have even considered using them in your garden. Eggshells contain vital nutrients beneficial to your garden. They are composed of 94 percent calcium carbonate, 4 percent organic matter, 1 percent magnesium carbonate, and 1 percent calcium phosphate, explains Scientific Reports. Putting eggshells to practical use in your garden saves them from filling landfills and helps your garden too.

Eggshells are beneficial to your garden in several ways. They add organic matter to the soil, help to raise soil pH, add calcium to the soil to help combat blossom end rot in tomatoes and peppers, and can be used to deter garden pests too.

Knowing how to prepare and use eggshells in your garden can lead to a more productive garden while avoiding sending your eggshells to the landfill, too.

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How do you prepare eggshells for the garden?

If you have ever tossed whole eggshells in the compost bin, you already know that they take a long time to decompose on their own. But that doesn’t mean you should give up on using eggshells in your garden. With some preparation, you can turn your eggshells into a useable product for your garden.

How you prepare eggshells for the garden depends on how you intend to use them. For a soil amendment to raise the soil’s pH or add the vital nutrient calcium to the soil, you will need finely ground eggshells. The eggshells must be coarsely crushed with some sharp edges to use as a deterrent to garden pests as mulch eggshells can be in larger pieces.

Methods for Preparing Eggshells for the Garden

The first steps to preparing eggshells for use in the garden are the same regardless of how you intend to use them. Follow these steps for getting your eggshells ready to use in your garden.

Wash the eggshells to remove any egg residue and let them air dry. This prevents the eggshells from getting smelly before you process them.
Store the washed eggshells in a bowl or other container until you have enough to work with. If you will be storing them for more than a day or two, store them in the fridge.

Spread the eggshells out on a baking sheet or baking pan so there is space between the shells. This allows for good air circulation and speeds the drying process.
Put them in the oven on low heat for an hour or two, or until they are completely dried. This thoroughly dries the shells and kills off bacteria lingering on the shells.
Allow the eggshells to cool.

Process the eggshells according to their intended use as outlined below.

How do you use eggshells to add organic matter to the soil?

Eggshells are a valuable source of organic matter and can improve the texture of your garden soil. When used wisely, they can improve aeration and drainage while slowly releasing nutrients into the soil.

To use eggshells to add organic matter to the soil, you can either crush them lightly and toss them into the compost bin to be used as compost later or break them down a little more and add them directly to the soil. Sections of the eggshell should be broken down to ¼ to ½ inches.

How do you use eggshells to raise the soil pH?

Many gardeners use ground eggshells as an inexpensive alternative to garden lime to raise the pH of their garden soil. However, eggshells need to be in a powdered form before being used to raise the soil pH.

There are several ways to grind up your eggshells.

Use a blender. Add the dried eggshells to the blender and pulverize them until they form a loose powder. The powder will be slightly gritty.

Use a mortar and pestle. If you are processing a small batch of eggshells, using a mortar and pestle is an effective method of grinding them into powder. This may be an appropriate method if you are grinding 10 or 20 eggs which are enough to make a gallon of liquid fertilizer.
Use a rolling pin. This method is better suited if you need coarsely ground eggshells but can be used to powder the eggshells with a little work and patience. The rolling pin method will work if you don’t have access to a blender.
Use a coffee grinder. Using a coffee grinder is also an effective way to grind your eggshells into powder.

How do you use eggshells to combat blossom end rot in tomatoes and peppers?

Blossom end rot is caused by a lack of sufficient calcium in the plant cells on your tomato and pepper plants, explains the Michigan State University Extension. It can result from a calcium deficiency in the soil but be aware that it is most often caused by improper watering that inhibits the plant’s ability to uptake calcium from the soil.

If your soil lacks calcium, it may contribute to or cause blossom end rot. In this case, using eggshells to add calcium to the soil can be beneficial to your tomato and pepper plants and may prevent blossom end rot.

To use eggshells to combat blossom end rot, you will need to use powdered eggshells as described above. Sprinkle the powder in the planting hole and mix it in with the existing soil before planting your tomato or pepper plants in the spring.

How do you use eggshells to deter cutworms and slugs?

Cutworms are the larvae of several moth species. They are called cutworms because they emerge from the soil in the spring and cut young seedlings off at the soil level. Cutworms can wipe out a whole row of young veggies in a night. Likewise, slugs attack and eat the foliage of tender veggies under the cover of darkness, too.

Many gardeners report success with using crushed eggshells around their young seedlings to deter both cutworms and slugs. While there is little scientific evidence to support the use of eggshells to deter cutworms and slugs, it is thought that the sharp edges of the eggshells damage these garden pests’ tender skin and discourage them from seeking out your veggies.

Spread coarsely crushed eggshells with sections that are ¼ to ½ inch in size around the base of seedlings to deter cutworms. Spreading a wide band of crushed eggshells alongside the rows appears to work best for deterring slugs.

How do you use eggshells to deter cats from using your garden as a litter box?

If your friendly neighborhood cat seems to think your garden is his new litter box, spreading crushed eggshells around the perimeter of your garden may send him on his merry way. Because cats don’t like the feel and sound of walking on eggshells, they reportedly seek out other areas and keep their distance from the garden.

How do you use eggshells as mulch?

If you have an excess of eggshells, you can use them for mulch under your garden veggies and flowers. Mulch helps to retain moisture in the soil and functions as a weed barrier, too. Keep in mind that to effectively work, the layer of mulch should be 2 to 3 inches deep. You will likely need a lot of eggshells to use as mulch in your garden or flowerbed.

However, it won’t take much mulch to cover the tops of containers and large pots or to mulch around a prized plant.

How do you use eggshells as liquid fertilizer?

Making liquid fertilizer from eggshells isn’t difficult, and it gives you a useful source of calcium for your plants. This can be accomplished in one of two ways. Choose the method that works best for you.

How to Make Liquid Calcium Fertilizer from Powdered Eggshells

The calcium in eggshells is in the form of calcium carbonate, which is insoluble in water. This means that your plants can’t access the calcium unless it is broken down to usable calcium. In this recipe, you will use a small amount of distilled white vinegar to break the calcium down into a usable form. Here’s how to do it.

Put two tablespoons of powdered eggshells in a small non-metal bowl.

Add two tablespoons of white distilled vinegar to the eggshells and mix with a non-metal utensil. The mixture will begin to bubble as the vinegar works to break down the shell and release usable calcium.
Let the mixture rest for about an hour, occasionally stirring to keep the mixture active.
Pour a quart of water into a gallon jug.

Add four tablespoons of the powdered eggshell and vinegar solution to the water.
Cap the jug and shake it to distribute the mixture in the water.
Fill the jug to the top with water and shake it again.

Water your plants with the liquid calcium fertilizer.

How to Make Eggshell Tea from Whole Eggshells

Many gardeners prefer this simple recipe for making eggshell tea for their garden because you don’t need to process the eggshells before making the tea.

Gather the eggshells from 10 to 20 eggs.

Place the eggshells in a large pot with one gallon of water.
Bring the mixture to a rapid boil.
Turn off the heat and allow the eggshells to soak in the water overnight.

Strain the eggshells and use the eggshell tea when you water your plants.

Note: It may be beneficial to add two tablespoons of white distilled vinegar to the solution when boiling the eggshells to help break down the calcium carbonate in the shells to a more readily usable form of calcium for your plants.

Where can you get eggshells?

If you want to incorporate eggshells into your gardening pursuits but don’t eat enough eggs to make it worth your efforts, you may be wondering where you can get eggshells.

Restaurants, bakeries, and other food service industries often pay to have their eggshells transported to the landfill and may be willing to give you their old eggshells. Check with local food establishments in your area to see if they are willing to save their eggshells for you.

How do you store eggshells for the garden?

If you have a surplus of eggshells or just want to know what to do with your everyday eggshells until you have enough of them to use, you may be wondering how to store them before using them in the garden.

Wash the eggshells thoroughly to remove any egg residue clinging to the shell. You don’t need to use soap or detergent, but you should make sure the surfaces are clean.

Place the shells in a bowl and store them in the refrigerator until you have enough shells to process. Typically, you will need at least 10 to 20 eggshells to make your efforts worth it.
Store dried and crushed or powdered eggshells in an airtight container or canning jar.

Does planting seeds in empty eggshells help the plants?

Planting seeds in eggshells can be a fun project for kids and makes an attractive display when the seedlings emerge, but it isn’t very practical. The tiny seedlings outgrow the shell quickly and must be transplanted into a pot.

Planting seeds in eggshells doesn’t provide any special benefit to the seedlings. If you choose to plant seeds in eggshells, try starting cat grass in eggshells displayed on the windowsill to welcome spring and some life to the home.

Sources

https://www.nature.com/articles/s41598-020-59324-5

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