Egg shells for plants

Photography by Justine Hand for Gardenista.

Above: All winter long I’ve been saving eggshells by simply rinsing them and placing them in an open container where they could dry out. (No, they do not smell. Everyone who comes to my house and sees them asks me this question.)

When my containers are full, I set the kids to pulverizing them into little bits with wooden spoons, thus compacting the shells so that I can collect more.



Above: When tilled into the soil, ground eggshells provide your plants with calcium.

Though nitrogen, phosphorus, and potassium are most vital for healthy growth, calcium is also essential for building healthy “bones”—the cell walls of a plant. Composed of calcium carbonate, eggshells are an excellent way to introduce this mineral into the soil. To prep the eggshells, grind with a mixer, grinder, or mortar and pestle and till them into the soil. Because it takes several months for eggshells to break down and be absorbed by a plant’s roots, it is recommended that they be tilled into the soil in fall. More shells can be mixed into your soil in the spring.

By the same token, finely crushed shells mixed with other organic matter at the bottom of a hole will help newly planted plants thrive. (Tomatoes especially love calcium.) For an exciting recycled garden cocktail, try mixing your eggshells with coffee grounds, which are rich in nitrogen.

Finally, eggshells will reduce the acidity of your soil and help to aerate it.

Seed Starters

Above: Because they are biodegradable, eggshells make excellent, no-waste seed starters. For this, reserve some of your deeper shell halves. Sterilize the shelves by boiling them or by placing them in a 200°F oven for 30 minutes. (If you put them in a cooling oven after, say, you baked a roast chicken, you can sterilize eggs without using excess energy.)

Next, with a nail or awl, make a hole in the bottom for drainage. Add soil and seeds according to the packaging. When sprouts appear, plant them—egg and all—right into the soil. See a complete DIY at 17 Apart.

Pest Control

Above: A coating of crushed eggshells in the garden is said to help deter several pests, both large and small. Deer dislike the smell of the albumen and will stay away.

Apparently you can also use egg’s insides to deter deer. See DIY: Homemade Deer Spray. Be aware, however, that while deer hate the smell of eggs, rodents love it. Therefore, it may not be best to use this deterrent near the house.

Many gardeners also tout the use of crushed eggshells as a snail and slug repellent. But a recent test by All About Slugs in Oregon seems to have dispelled this. If you’ve had any success with eggshells as slug repellent, we’d be curious to know.

Bird Food

Above: Like plants and people, birds also benefit from a bit a calcium in their diet, especially the females who need extra before and after laying their eggs. To make bird food, start by sterilizing the shells by leaving them in a cooling oven after you bake a meal. Then crush them into fine bits and mix with your favorite seed.


Above: Like oysters, eggshells used as mulch provide a striking accent in the garden. If you gather enough, you can even apply a layer thick enough to deter weeds.

Looking for more recycled garden how-tos? See our guide to Edible Gardens 101 and more posts:

  • Dirty Secret: 10 Ways to Improve Garden Soil
  • Seafood for the Garden: Make Your Own Organic Fertilizer
  • Gardening 101: How to Use Fallen Leaves
  • How to Sprout Seeds and Grow a Compost Garden

Should We Add Eggshells to the Garden?

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  • The popular advice to improve plant health with eggshells is misleading (modern garden folklore).
  • The idea that calcium is deficient in soil, that eggshells instantly provide it, and plants take it up and flourish are all problematic.
    Soil tests rarely indicated calcium deficiency. If a plant is truly calcium deficient, it is often an uptake problem, which is not solved by adding more.
  • Eggshells are just one of many organic foods we can compost, contributing micronutrients and structure, taking many years to break down.
    Fine to include in compost (like many other things) but not a magical superfood.
  • Correlation is not cause: just because you added eggshells and plants did well does not mean that was the cause.

Do Eggshells Really Give Plants a Boost?

So, are eggshells good for your garden? Plenty of people think so, but the short answer seems to be, no, not really, and whatever benefit they theoretically might provide can be much better achieved in other ways.

It’s easy to understand why this gardening myth refuses to die.

Eggshells are calcium!

Calcium’s good for you! Builds strong bones!

So, let’s put it in the garden!

And, it’s not entirely a myth. Your plants do need calcium and eggshells provide it—that part’s true! But, there’s probably plenty of calcium in your soil already, so adding more calcium isn’t going to help at all.

And, even if extra calcium would help, eggshells aren’t the best way to do it.

Unless you grind them to a very fine powder, they’re just going to sit in your soil as broken eggshells for years until they decompose.

Now, they will eventually decompose, so maybe they’ll help your plants many years from now—again, only if your soil was calcium deficient—which it probably won’t be.

That said, the eggshells aren’t going to do any harm, and composting them is better than sending food waste to landfill, but just don’t expect to see any improvements in your garden because of them.

If anyone tells you their plants changed quickly after adding eggshells to the soil, now you know that the eggshells were not the cause.

Related: Beginner’s Guide to Organic Fertilizers

Eggshells can be used in a variety of ways to enrich your garden. Eggshells provide a valuable source of calcium for growing plants and also deter certain pests without the need for chemicals. Eggshells consist of 93% calcium carbonate and other trace elements that make them a practical fertilizer. The composition of an eggshell is very similar to that of our bones and teeth. A medium sized eggshell makes about one teaspoon of powder, which yields about 750 – 800 mgs of calcium. Eggshell calcium is probably the best natural source of calcium, and it is easy for the human body to digest and absorb too. In fact many people eat powdered egg shells as a dietary supplement.

Likewise your plants can also benefit from this source of calcium. In the garden, for fertilization purposes make sure you crush the eggshells before you add them to your garden. Crushing the eggshells helps them to break down so that they may readily supply calcium to your plants. Without adequate amounts of calcium, plants experience a variety of problems. If calcium is deficient the cell walls of a plant become weak and unstable. The stronger the cell wall, the stronger the plant, and the quicker its recovery from the enormous pressures that it is faced with in the garden. This applies for both leaves and roots. The stronger the root cells are, the more aggressively the roots will be moving through the soil. Sufficient levels of calcium also assist in the efficient use of sunlight, carbon dioxide, water, nitrogen and minerals. Calcium also plays a major role in the construction of numerous hormones, and enzyme systems that can help protect the plant from insect and disease attack.

To prepare, your eggshells should be washed first or they could attract pests into your garden. Put the shells in a plastic bag and then crush them by hand, if you are really dedicated you may then powder them in the blender if desired. The powdered or crushed eggshells are best placed around fruit trees, tomatoes, roses and in potted plants, though it will be of benefit anywhere in the garden! The powder is very useful for tomatoes because the extra calcium will help prevent blossom end rot. This is a condition which causes tomatoes and other vegetables to develop black patches on one end. Blossom end rot is caused by insufficient calcium or poor absorption, so a ready supply at root level is a good preventive measure.

Sprinklings of crushed eggshells can be added and tilled directly into the garden soil. They can also be added to the soil mixture of seedlings or to the bottom of potted plants. The water used to cook hard boiled eggs is also a valuable source of calcium. Allow the cooking water to cool to room temperature and then simply pour it around the base of vegetable or house plants to provide added nutrients. Alternatively you can soak the crushed eggshells in water for a few days to make a ‘calcium tea’ to feed your plants with.

Crushed eggshells can also naturally assist in deterring some pests from a vegetable garden. There is nothing worse than growing a vegetable or fruit from seed only to come out one morning and see it has been eaten and destroyed by slugs or snails. Snails require a smooth surface to move. If they come across a barrier of sharp grit they will not be able to pass. The sharp edges of the shells can be deadly to any slithering creatures, such as slugs and cutworms. Spread crushed eggshells around the base of seedlings. When the pests such as snails or slugs make their way toward the plants, they will be deterred by the rough edges of the crushed shells. For organic growers this is also the best way to protect your plants, it is the cheapest easiest and most natural solution. Not only are you protecting your plants from being eaten and destroyed you are also giving them extra food as well.

Eggshells can also be used as planters for small seedlings and be put directly in the ground for planting. Make a small drainage hole in the bottom of an empty eggshell, with a pin. Add soil and put it in an open egg box. Sow the seeds and care for them as you would any other seedlings. The shell will provide a natural slow release fertiliser for your seed as it germinates. When the seedlings are ready to transplant into the garden, squeeze the shell gently to crack it and then place it in the ground. The roots will push through the cracks in the shell which will decompose naturally.

Another commonly discarded kitchen waste item is coffee grounds (tea leaves as well for that matter), which can be particularly useful in the garden. Used coffee grounds contain about two percent nitrogen, and many trace minerals. They are particularly useful on those plants for which you would apply an ‘acid food’ such as evergreens, azaleas, roses, camellias, avocados, and certain fruit trees. I store old coffee grounds in a tin and then scatter them lightly mainly around the roses. Don’t scatter them thickly when they are wet, because the coffee grounds have a tendency to get moldy.

Dr. Kris

Garden Doctor

Contact: [email protected]

Copyright © 2010 Dr. Kris

You can read all past articles of Garden Doctor at

Using Eggs As Plant Fertilizer: Tips For Fertilizing With Raw Eggs

Soil amendment is necessary in almost every garden. Low macro and micro-nutrients cause problems like blossom end rot, chlorosis and low fruit production. Organic gardeners like to turn to natural products for answers to common nutrient problems. Using eggs as a fertilizer is an old trick, but it can have some unpleasant secondary effects. Raw egg fertilizer may not be the best way to introduce calcium to your plants, but the shells are a bona fide true winner in the garden.

Fertilizing with Raw Eggs

Our grandparents didn’t have access to the modern formulations for soil amendment and instead relied upon composting to boost soil fertility and tilth. We can take a page from their book and learn how to reuse our refuse and give back to the soil naturally. A time honored tradition is to place a raw, uncracked egg in the bottom of a planting hole for tomatoes. It has its benefits and its drawbacks as we will see.

Benefits of Using Whole Eggs as Fertilizer

Eggs contain high levels of calcium. This is an important nutrient for plants, especially vegetables and fruits. Eggs will leach the calcium into the soil for root uptake during composting, which can conquer such problems as blossom end rot. However, excess nitrogen and low pH will tie up calcium in soil, preventing uptake.

Using eggs as a fertilizer imparts calcium but it isn’t useful if the plant can’t access the nutrient. Always check your soil pH before planting a new garden and minimize the amount of nitrogen you introduce to soil after buds start to form.

Potential Downsides to Raw Egg Fertilizer

One obvious problem to fertilizing with raw eggs is the smell. If you don’t bury the egg deep enough, over time it will begin to stink. Additionally, using whole eggs as fertilizer can attract unwanted pests. Raccoons and rodents will be attracted to the odor and dig out your baby plants in an effort to get to the potential food source.

Whole eggs as plant fertilizer aren’t the quickest way for your plants to get calcium because they take a while to break down. A better source is just from the shells, which are the main concentration of the nutrient. Use the eggs and save the shells for a quicker, less smelly way to keep your veggies from dropping blossoms.

How to Use Eggs as Plant Fertilizer

In order to avoid issues with fertilizing with raw eggs, just use the shells. These are usually discarded after the egg itself is cooked but carry a calcium charge for your soil. Simply crush the shells and mix them into soil.

Another way to use eggshells is to boil them and water with the resulting liquid. This prevents the issues raised about raw egg fertilizer while still enhancing the soil. The University of Minnesota performed a test using distilled water and boiled eggshells. The resulting water had increased levels of calcium and potassium, both of which benefit plants, especially those that flower and fruit. Using the water to irrigate plants provides an easy way for roots to access these nutrients.

You can also make a foliar spray so leaves will draw the nutrients into the vascular system to utilize both elements. So eat your eggs, save your shells and fix your soil for bigger, better vegetable crops.

Wondering what to do with all of those leftover Easter eggs that were so lovingly dyed and decorated? Consider adding the eggshells to your compost pile for extra nutrients. Learn about composting eggshells.

Wondering what to do with all of those leftover Easter eggs that were so lovingly dyed and decorated? Consider adding the eggshells to your compost pile for extra nutrients. Learn about composting eggshells.

It’s the week after Easter and if you’re like us, your family is probably enjoying a steady diet of hardboiled eggs and egg salad sandwiches. Rather than toss the eggshells in the trash, we wondered — can you compost eggshells?

For a basic compost pile it’s typically best to stick with composting plant-based kitchen scraps like vegetable peels, coffee grinds, or even grains. Meat and dairy products in general should be avoided because they quickly become rancid and can attract unwanted pests and animals. But what about composting eggshells?

While eggshells do have the potential to attract critters to the compost bin, they are a source of valuable nutrients and calcium. Eggshells can be added to the compost pile with just a few extra steps for added precaution.

If your family went to town decorating Easter eggs, it might be a good idea to stay away from eggshells that have glitter, stickers, or other decorative embellishments that generally should be avoided in compost piles.

Eggs can harbor Salmonella so it’s best to wash the eggshell in warm water before adding it to the pile. You definitely don’t want Salmonella bacteria spreading in your garden! Others take an extra step and bake the eggshells in the oven for about 20 minutes to make sure the Salmonella is destroyed. The heat doesn’t destroy the calcium in the eggs.

Grind or crush the eggshells into small pieces before adding it to the compost bin. This will help the eggshell break down quicker and will be easier to mix in with the rest of the kitchen scraps.

Lastly, while it’s OK to compost eggshells, it’s still a good idea to leave out the rest of the egg. In addition to attracting animals, the other egg parts can give the compost pile a funky smell that would be best to avoid.

Check out other kitchen scraps you can compost.

Eggshells In The Garden: Using Eggshells In Soil, Compost And As Pest Control

Many people don’t know that using eggshells in the garden can help in many ways. If you are wondering what to do with crushed eggshells (or whole eggshells for that matter), keep reading. We will look at how eggshells can help your compost, soil and even keep away a few common pests.

Eggshells in Compost

A common question is can you put eggshells in compost heaps? The answer to this is yes, you can. Adding eggshells to compost will help add calcium to the make up of your final compost. This important nutrient helps plants build cell walls. Without it, plants cannot grow as fast, and, in the case of some vegetables like tomatoes and squash, fruit will develop blossom end rot because there is simply not enough building material (calcium) coming into the plant. Using eggshells in the vegetable garden compost can help prevent this.

While you don’t need to crush eggshells before composting them, doing so will speed up how fast the eggshells break down in the compost. You also may want to consider washing your eggshells before composting them so that you do not attract animals, as well as reducing the slight risk of disease which raw eggs pose.

Eggshells in Soil

Eggshells can also be added straight to the soil. Many people plant eggshells with tomatoes, peppers, squash and other vegetables that are susceptible to blossom end rot. While planting eggshells directly with plants most likely will not help this season’s plants (because the eggshells will not break down fast enough to create calcium), eggshells in the soil will decompose eventually and will help add calcium directly to the soil.

Using Eggshells in the Garden for Pests

Eggshells can also be used in the garden to help fight off pests like slugs, snails, cutworms and other crawling pests. Crushed eggshells works much like diatomaceous earth on these pests. When crawling pests cross over an area in the garden where crushed eggshells have been spread, the eggshells make several small cuts in the pests. The pests then dehydrate and die due to these cuts.

Crushing eggshells for pest control is as easy as tossing your empty eggshells into a food processor for a few seconds or just rolling them under a bottle or rolling pin. After the eggshells are crushed, sprinkle them around the areas in your garden where you are having problems with slugs and other crawling pests.

Using eggshells in the garden is a great way to make use of something that would normally just get thrown out. You can put eggshells in compost, in soil or use them as a kind of organic insecticide, which means that not only are you helping reduce trash, but helping your garden too.

Can I Compost Eggshells

Can I Compost Eggshells?

Composting Eggshells in the HOTBIN

A popular composting question we get asked is whether eggshells will compost in the HOTBIN. Although it may seem like a myth, like most things, eggshells do break down over time and this article covers the science behind why we say they can be added into the HOTBIN.

What Does an Eggshell Consist Of?

For those who don’t know, an eggshell is a natural source of calcium with the shell made almost entirely from calcium carbonate – it’s one of nature’s great designs really!

Calcium carbonate can be likened to lime/chalk, which although difficult to digest by bacteria in a cold compost heap, is susceptible to heat. This exposure to heat causes the shell to soften and weather resulting in it becoming brittle.

Benefits Adding Calcium to Soil

The process of liming is well known to seasoned gardeners. This is where lime is added to acidic soil to increase calcium content, raise soil pH and improve soil quality.

Similarly to a human diet where calcium is needed for strong bones, calcium is essential for supporting cell growth in plants to ensure strong plant walls and healthy growth.

Different Uses for Eggshells

Eggshells provide further benefits such as enhanced aeration when added directly into the soil. It is claimed that eggshells act as a slug deterrent because of the sharp surface they create for the pests – conversely however you do run the risk of attracting rodents into your garden who are looking for a free snack.

If you fancy being creative, half shells can be used as starter pots for seedlings providing them with calcium benefits from the very start.

Whatever the use, the general advice for using eggshells on the garden is to wash, dry and grind and be prepared for them to take a while to breakdown.

How to Compost Eggshells in the HOTBIN

If adding eggshells into the HOTBIN it is recommended that they are crushed into fragments before adding. When processed inside at temperatures of 40-60°c the heat inside the HOTBIN causes the shell fragments to become brittle encouraging them to breakdown much faster than they would have done if the shells had bypassed the hot composting process.

When harvesting a batch of HOTBIN compost you may well still see small bits of shell, these however will be quite brittle which means when added to flower beds they will break down/crumble quickly releasing calcium into the soil faster too.

All other types of shells can be added into the HOTBIN too such as mussel, crab and cockle shells to name but a few.

Using Eggshells

Costa Georgiadis

COSTA GEORGIADIS: Lots of people ask me, “Can I compost eggshells?” And the simple answer is, “Yes.” Anything organic can be composted and in the case of eggshells, they’re packed with the mineral calcium, which plants and all those critters in your compost, such as worms, absolutely love.

You can put them straight in to the compost but you’ve got to remember that worms only have tiny mouths so it’s better if you crush them up beforehand.

The other thing I like to do is to create a supply of slow-release calcium such as this so that I can mix it in with my potting mix for plants such as citrus, which love their calcium.

But there’s a trick to this. If you get your eggs straight after you’ve used them, and you crush them up, the little bit of egg that sits in the bottom will go mouldy and you won’t end up with a nice container like this.

So give it a little bit of a clean out, allow them to dry on the window sill or put them in the oven after you’ve been baking, they’ll dry. I put them in the blender and presto and look at that – beautiful crushed calcium ready to spread into my potting mix.

And here’s another little trick – when you crack your eggs open, crack them higher up so that you’ve got a nice little container and you can use it to start your seedlings in. Another way to egg-stend your garden budget.

This method uses water and eggshells to yield a cheap, nutrient-rich tea for your houseplants and garden.

Eggshells are no stranger to the gardener – whether they are used to start seedlings or crushed to add nutrients to soil, many a plant-lover puts eggshells to use. But I especially like this method of making an eggshell tea (yum!) to use as an all-natural and inexpensive fertilizer that can be used for houseplants or in the garden. Not only does it give our green friends a good boost of calcium, but it gives eggs one last hurrah before heading to the compost.

Calcium is an essential plant nutrient, and as explained in a paper in the Annals of Botany, a calcium deficiency can lead to all kinds of problems, like: “tipburn” of leafy vegetables; “brown heart” of leafy vegetables or “black heart” of celery; “blossom end rot” of watermelon, pepper and tomato fruit; and “bitter pit” of apples. And nobody wants black hearts and bitter pits in their garden.

And a good point that Emily Weller notes in SFGate, “Unlike synthetic fertilizers, when you use eggshells in your garden, you do not have to worry about going overboard.”

• In a large pot, boil a gallon of water and add 10 to 20 clean eggshells to it.
• Turn off heat.
• Allow the brew to sit overnight, then strain.
• Pour the tea on plant’s soil.
• Apply once a week.

Eggshell is made almost entirely of calcium carbonate (CaCO3), which is a common form of calcium, and the most common form of calcium found in nature (think seashells, coral reefs and limestone). It is also the cheapest and most widely available form of calcium in supplements. And here we are, just throwing it away! Eggshells contain small amounts of other minerals as well. When Master Gardener Jeff Gillman, author of “The Truth About Garden Remedies,” sent a batch of eggshell tea to the lab, the results showed that it contained 4 mg of calcium and potassium, as well as very small amounts of phosphorus, magnesium and sodium, reports Weller.

If the eggshell infusion does not appeal to you, you can also crush the shells into a rough crumb or powder. Wash the shells well and crumble them with your hands or grind with a mortar and pestle, food processor, blender, et cetera. Mix it into the garden soil or potting mix.

Lastly, for the least amount of work, you can sprinkle crushed shells (crushed to confetti size) around the garden – this is rumored to be especially good if you have a slug problem, as they are said to not enjoy the sharp edges.

For more all-natural gardening ideas, see related stories below.

Via Southern Living

Lots of Plants Besides Tomatoes Love Eggshells. Slugs Don’t.

Lots of Plants Besides Tomatoes Love Eggshells. Slugs Don’t.
Q. Eric from soggy Ellicott City, Maryland (how soggy is it? His email was wet!) writes: “One of the tips I’ve picked up from your podcast is to sprinkle crushed eggshells into the planting holes of my tomatoes. I’ve been saving my eggshells ever since and have a few crushed quarts of them. My problem is that I only plant a couple of tomatoes a year. Can I use my stockpile of eggshells elsewhere in the garden? I grow mostly flowers – are eggshells useful for flowers? What about flat earth and raised bed flowers and vegetables? Is there anything that wouldn’t benefit from a bit more calcium, or is it possible to have too much of a good thing?”
A. Perfect time of year for this question, Eric, as many of our new listeners may not know ‘the old eggshell trick’ and this gives them time to amass the number of shells they’ll need for tomato planting season.
To wit: Placing crushed eggshells in the planting hole of tomatoes provides two distinct benefits: 1) It totally prevents blossom end rot, one of the worst tomato tragedies, when tomatoes that are almost ripe suddenly turn black on the bottom (‘the blossom end’) and fall apart. Greenhouse growers can avoid this problem by supplying even amounts of water during the growing season because their plants are not exposed to rain. But those of us growing out in the open can’t possibly avoid the ‘uneven watering’ that causes the problem–but we can add eggshells. When tomatoes have adequate soil calcium, they can control their internal water movement enough to avoid the extreme pressures that cause the blossom end to burst. Over the years, I’ve found crushed eggshells to be the perfect way to supply this calcium. The shells release their calcium slowly over the season, providing a nice steady supply of the nutrient–and you weren’t going to keep them! Sure, you could add the shells to your compost pile, but they are reluctant to break down and are often the only raw ingredient left visible after the rest of the compost is finished. 2) Adequate soil calcium is also necessary for the finest-tasting tomatoes to develop the rich, full, complex flavors we’re seeking when we try and grow ‘the perfect tomato’. The basic flavor of every tomato is a blend of sweetness and acidity, but the super-tasty ones–generally old adored heirlooms like Brandywine, Black Krim and Mortgage Lifter–also develop complex volatile aromatic oils that lend distinct–and delicious–‘back flavors’ to the fruits. They can’t do this without calcium; and again, crushed eggshells are the perfect slow release form of that nutrient. So, save up your eggshells. After you’ve finished a carton of eggs, let the shells air dry out in the open for a day or two (no need to rinse them; they don’t smell). When tomato planting time comes around, dig a deep hole for each transplant, pull off all the bottom leaves, drop the transplant down into the hole, finely crush a dozen dried eggshells overtop of the rootball, then fill the hole back up with the same soil you removed–no ‘improved soil in the hole’; then mulch with two inches of compost and provide good support for the vining plant.
Next in line to receive any eggshell largesse is your cucumber crop. In this case, dig a regular sized planting hole (tomatoes are the only plant whose stem gets buried deeply), drop your baby cuke plants into the hole, add a dozen crushed eggshells, fill the hole back in with the soil you removed and then mulch with compost. The calcium in the eggshells will make your cucumbers naturally crisper–both raw and after they’re pickled!
After that, there are a surprising number of ornamentals that want either supplemental calcium or a slighter higher pH (which the crushed shells also provide). The numbers are kind of mind-boggling–there are several large books devoted exclusively to flowers that prefer alkaline soil!
Here are some of the best-known candidates:
&nbsp • Lilacs
&nbsp • Bluebeard (caryopteris)
&nbsp • Clematis
&nbsp • Forsythia
&nbsp • Barberry (just stick to the non-invasive cultivars bred not to produce viable seed)
&nbsp • Crocus
&nbsp • Red Tip Photonia; &
&nbsp • Buddelia (Butterfly Bush)
The greatly-misunderstood boxwood also falls into this category, as despite being evergreen, it suffers in soil that isn’t on the alkaline side. If you’re out of eggshells at this point, ask a friend with a fireplace or wood stove for some of their ashes. Ashes from a hardwood fire are almost as alkaline as agricultural lime. And boxwood loves wood ash.
And finally, if you’re NOT out of eggshells yet, crush them up very finely and use them to make a ring around slug-prone plants like lettuce, potatoes and hostas. Slugs are extremely weird creatures–copper gives them an electrical shock; diatomaceous earth (DE) dehydrates them; they can’t metabolize iron (used to make non-toxic slug baits)…
And eggshells are doubly deadly to the slimers. Their bodies can’t handle the calcium in the shells and the microscopically sharp edges of the crushed shells (so small that we can’t see or feel them) tear them apart if they try and cross over them (much like DE).
One final note: Make sure your soils aren’t already alkaline before you add anything to up the pH; and never ever use eggshells or other pH-raisers around acid-loving plants like azaleas and rhododendrons.

Five Ways to Use Eggshells in Your Garden

A normal person looks at an egg and thinks “omelet” or “frittata.” A gardener (especially one who tends to be on the obsessive end of the spectrum) looks at an egg and thinks “yes! Eggshells!”

Five Ways to Use Eggshells in Your Garden


1. Add crushed eggshells to the bottom of planting holes, especially for tomatoes, peppers, and eggplant. These crops are susceptible to blossom end rot, which is caused by calcium deficiency. While this deficiency is most often caused by improper watering, there’s no harm in making sure your plants have a steady source of calcium. As the eggshells break down, they’ll nourish the soil, and your plants.

2. Use eggshells as pots for starting plants from seed. Then plant the seedling, “pot” and all, into the garden.

3. Use crushed eggshells to deter slugs, snails, and cutworms. These garden pests are a real pain in the gardener’s neck, and cutworms are the worst, killing seedlings by severing the stems at soil level. All three of these pests have soft undersides, and dislike slithering across anything sharp. Crushed eggshells, applied to the soil’s surface, may help deter these pests.

4. Add them to the compost pile. If you aren’t planting tomatoes or trying to deter slugs, add the eggshells to your compost pile, where they’ll add calcium to your finished compost.

5. If you are feeding birds in your yard, crush up the eggshells and add them to a dish near the feeder. Female birds, particularly those who are getting ready to lay eggs or recently finished laying, require extra calcium and will definitely appreciate it!

No matter how you want to use them, be sure to rinse the shells out well before using them in the garden.

Watch Video: Sara Snow: The Top Organic Veggies

Did you know that you can use eggshells in the garden?

Crushed eggshells can add valuable nutrients back into the soil with the high-level of calcium being very beneficial to the plants. Read these excellent uses of eggshells in garden.

#1 – Adding Eggshells In Compost

A popular question is… Can eggshells be added to compost bins and heaps? And the answer to the question is YES. Adding crushed eggshells to compost helps to add calcium to your final compost.

This essential nutrient helps in building cell walls in plants. Without it, plants will not experience vigorous growth.

In vegetable plants such as squash and tomatoes, fruits will develop a blossom end rot because of deficiency of building material (Calcium) in the plant. Adding eggshells in the vegetable garden compost can help prevent this.

While it’s not a must to crush your eggshells before adding them to compost, doing so will speed up their breakdown process in the compost.

You also may consider washing your eggshells before adding them to compost so that they don’t attract animals. Washing them will also reduce the risk of disease posed by raw eggs.

All the minerals in eggshell can be found in the soil and the addition of these minerals will help neutralize the pH level of your compost. The good thing with eggshell is that they do not add alkalinity to your soil, but neutralize it.

#2 – Using Eggshells As Fertilizer

When eggshells are tilled into the soil, your plants will benefit from calcium minerals. Though phosphorous, nitrogen and potassium are the most vital minerals for healthy growth; calcium is essential to give plants a strong and robust growth.

As aforementioned, calcium helps plants build cell walls.

Eggshells are composed of calcium carbonate, which makes them an excellent way to introduce calcium into the soil. To prepare eggshell, grind with mortar and pestle, grinder, or mixer, and till them into your garden soil.

It’s recommended that they be added before the planting season as they take several months to break down and be absorbed by the roots. Therefore, add them in the fall and spring.

However, during the time of planting, you can add finely crushed shells together with Epsom salt which tomatoes love along other organic matter at the bottom of the hole to help the newly planted seedlings thrive (Tomatoes enjoy the extra calcium from the egg shells).

For a more useful recycled garden cocktail, you can mix your eggshells with coffee grounds; these are rich in nitrogen. By adding eggshell fertilizer, you’ll be reducing the soil acidity and aerating it at the same time.

You can also add grounding eggshell powder to your watering can and stir it up. Water your plants with the calcium enriched water.

#3 – Adding Eggshells In The Garden For Pest Control

Coarsely smashed eggshells can form an effective barrier against soft-bodied pests like slugs and snails. They do not risk passing over the uncomfortable and sharp spiky shells.

To do this, arrange the crushed layer of eggshells around those plants known to be sensitive to such pest.

Also, deer dislike the smell of the egg albumen and will stay away from gardens with the egg smell.

However, be aware that though the smell may keep deer at bay, it may encourage the rodents near them. Therefore, don’t use it near the house as you might experience a rodent influx in the compound.

For flying pests, you’ll need to crush finely and grind your shells in a blender or food processor. The eggshell dust will get into the beetles and other garden pests with wings thereby acting as glass for them.

You can also sprinkle the entire plant with finely ground or hand ground eggshells depending on the pest you intend to deter.

You’ll need to reapply the powder more often; so keep you eggshells and reapply them to your plants or garden after some time.

#4 – Make Eggshell Plant Starter Containers

Because of their biodegradable nature, eggshells make excellent seed starter planter. To do this, reserve a good number of deeper shell halves.

You need to sterilize them by placing your eggshells in a 200-degree oven for about 30 minutes or boil them.

After this, make a hole in the bottom using an awl or nail. This will help with drainage. Add seeds and soil according to the packaging instructions.

When your seedlings sprout, transfer the whole eggshell and seedling, into the soil. This will give your seedlings a boost because of the mineral-rich nature of the eggshell.

#5 – Include Eggshells In Bird Food

Like people and plants, birds also benefit from calcium in their diet, especially the females as they need calcium to lay eggs.

To make bird food, sterilize your shells as mentioned above and then crush them into fine bits. You can mix them with your favorite seed.

#6 – Add To Chives

Eggshells can be added to chive especially those planted in pots or containers. Drop a handful of crushed shells around the roots. The shells will decompose gradually thereby providing more calcium that the chives.

#7 – Help Aid Tomatoes Prevent Blossom End Rot

Eggshells are an excellent source of calcium, a crucial nutrient to prevent blossom end rot. Tomato blossom end rot is a cultural problem that occurs when there’s a calcium deficiency.

The deficiency affects the plant’s ability to regulate and control the moisture intake.

While the use of eggshells for preventing this problem is not scientifically proven, it can’t hurt to give a try.

So, stave off the disappointment of harvesting black, wilted end by adding the eggshell powder to your tomatoes. The powder will boost your chances of harvesting perfectly ripened and reddened tomatoes.

How Do You Process The Eggshells Around Your Home?

The first thing to do is pasteurize the eggshells. It’s better to be safe than sorry especially when it comes to raw eggs.

The process is simple and bit smelly, but it’s worth it. Before crushing your eggshells, heat them for 10 minutes in a 200-degree oven. This will keep the salmonella at bay.

Crush and grind your shells – after pasteurizing your eggshells and they’ve cooled, you can use your hands to crush them before transferring them to the blender grinder attachment for further grinding.

You can also use a blender, coffee grinder, or a mortar and pestle. Another physical way of crushing the shells is by putting them in a plastic zipper bag and crushing them with a rolling pin until they’re a fine powder.

Why Does This Matter?

Eggshells are composed of more than 95% of essential minerals. Calcium carbonate is the main mineral (37%) which is an essential mineral needed to ensure optimal plant growth. It almost has the same effect as the banana peels but the mineral content is different.

They also have significant amounts of potassium, iron, magnesium and phosphorus making them an excellent addition to your garden soil.

Making use of the eggshells in the garden is an economical way to recycle something that is normally seen as waste.

Add it to your compost pile or compost bin, bird feeder, soil, or use it as seed starters or pest repellant.

Want ideas on how to use eggshells in the garden other than just for composting? Help yourself to these practical and cost-cutting ways to maximize your eggshells.

RELATED: Guaranteed Healthy Organic Compost With These 25 Natural Ingredients

How to Use Eggshells in the Garden in 15 Smart Ways

Amazing Ways to Use Eggshells in the Garden

Can you keep track of the eggs consumed in your household? From cooking the family’s favorite egg omelets and pancakes to baking your delicious deviled eggs, cakes, and pastries, eggs are never absent at home.

It’s no secret eggs are healthy for us, but did you know they’re healthy for the garden too? The eggshells, at least, of which I am in no short supply.

If you happen to be curious as to how to make use of these eggshells that you think don’t serve much purpose once cracked, then lucky you! I’ve been practicing some of these gardening ideas myself.

Find out how to use eggshells in the garden and cut back on gardening costs with this infographic:

1. How to Use Eggshells in the Garden Compost

Eggshells are organic compost material valued in the garden for its hefty calcium content beneficial to the soil and plants. They are green compost materials that comprise only a third in a healthy and balanced compost.

But don’t throw the rest of the eggshells away because I still have several more great ways to use eggshells in the garden.

To use eggshells for composting:

  1. They’re better crushed for a faster breaking down process. Put them in a bag and crush them with anything hard.
  2. You can also step on them, in your shoes of course, as eggshells can be sharp.
  3. Then spread them over or mix them with the rest of the organic compost materials.

2. Eggshell Pest Deterrent

Slugs and snails are among the most notable pests in any garden. They like to munch on tender leaves of vegetables and fruits.

To prevent these critters from invading the plants, spread crushed eggshells around them.

The slugs and snails will find the sharp edges of the eggshells such an impenetrable barrier they’ll abandon their quest.

Be careful, though, as the scent of rotten eggs could potentially attract scavengers like rodents instead.

3. Eggshells Seed Starting Pots

The idea of biodegradable seed-starting planters is truly ingenious. Eggshells are biodegradable, meaning they rot in the soil leaving their nutrients behind.

Instead of plastic seed-starting pots, why not use eggshells where they can just be planted along with the seedling. No more worries over having to disturb the roots of the plants or even destroying them.

If you find this a great plan for your own seed-starting projects, you’ll have to sanitize them first by pouring hot water over the shells. They can also be allowed to dry under the sun to save on utility costs.

Puncture tiny holes at the bottom of the shells for seed-starting. Then you can place them back up in the tray to let them stand.

4. Pretty And Dainty Eggshell Planter Ideas

Not only do eggshells make great seed-starting pots, but they also make nice planters for ornamental plants. Our favorite mini plants like cacti and succulents will feel at home in these equally cute planters.

Face Emoji Eggshell Planters

For the extra artsy gardeners, eggshells will make a great medium for crafts such as these silly emoji faces. Your imagination is your only limit to making great designs for these tiny planters.

Succulent Eggshell Planters

Succulents are enjoying some kind of popularity in home and garden design with their diversity. Take this succulent design for your indoor garden, with tiny succulents that could fit perfectly in tiny eggshell planters.

5. Eggshells for Your Stock Pot or Bone Broth

Did you know that adding eggshells to your vegetable stock or bone broth is highly beneficial for your health? Crushed eggshells are known for its calcium content but it also contains other minerals as well:

  • zinc
  • selenium
  • magnesium
  • iron
  • phosphorus
  • fluoride

Worried it will affect the taste of your bone broth? Don’t be. You get all this nutrition and the flavor stays the same.

6. Eggshells On Bird Feeders

Birds are more useful to your garden more than you think. They provide protection to your plants since they are natural prey to some of the most common garden pests.

Some bird species are also pollinators helping fertilize plants and bear fruits. Besides, the sight of them in the garden brings cheer and amusement.

We give back to them by putting up birdbaths and bird feeders.

Go extra further by providing them calcium supplements which they will appreciate. Sterilize and crush the eggs, then mix them with the seeds in the bird feeder.

7. Eggshells Garden Decor

I’ve seen this garden decor idea before in a Christmas garden decoration with Christmas balls in place of eggshells through the tips of Yucca leaves.

For a more organic approach to this simple design, it’s great to have eggshells in place of plastic balls. But the eggshells could also use a bit of design or painting.

8. Eggshells for Healthy Tomatoes

To promote healthy growing tomatoes, best to place a handful of coarsely crumbled eggshells under your tomato plants. The amount of extra calcium, minerals, and elements will be extremely beneficial to your tomatoes as they steadily grow throughout the season.

RELATED: Starting A Garden This Spring | Easy Gardening Tips And Tricks

9. Eggshells for pH Balance

Scatter finely ground eggshells all over your garden to balance out the acidity of your garden soil. The calcium carbonate found in eggshells can neutralize the pH balance of the garden soil if it is too acidic for your crops to grow.

It is important to note that hand crushed eggshells are not sufficient enough to change the pH and add calcium to the soil. Studies prove that the eggshells must be thoroughly ground in order to balance the pH and increase the soil calcium level.

10. Eggshells for Chicken Feed

Toss a handful of eggshells to your chickens if you want them to lay healthy eggs. The calcium from eggshells is beneficial for a vitamin boost, especially when laying eggs.

All you need to do is:

  1. Collect enough eggshells and dry them out at room temperature.
  2. Lay them out then crush the eggshells smoothly with a mortar and pestle.
  3. Place them on a baking sheet.
  4. Bake for ten minutes at 375°F.

11. Eggshells for a Great Coffee Experience

Did you know that ground eggshells make a fine addition to your coffee? The high heat when making campfire coffee runs the risk of boiling over the coffee grounds.

The eggshells will prevent this from happening. Also, when coffee is brewed long enough to make it very bitter, eggshells help make your coffee less acidic.

One egg’s worth of finely crushed shell is good for four cups of great coffee!

12. Eggshells for the Worm Bin

Eggshells are also useful in worm composting aside from the regular compost pile. If you’re into vermiculture, the worms will consume the crushed eggshells and convert this nourishment into worm castings.

These castings are highly nutritious and will help increase the pH of your worm bin.

13. Eggshells as Deer Repellent

Does deer frequently visit your precious garden in the dead of night? If so, scatter crushed eggshells around your garden perimeter to keep those deer from munching on your veggies.

Deer hate the smell of albumen or egg white, which will drive them away from your greens.

14. Extra Calcium for Your Dog

Crushed eggshells provide an extra source of protein and calcium for dogs. Here’s how:

  1. Place clean eggshells on a baking pan and bake for 30 minutes at 250°F.
  2. Put the baked eggshells inside a zipper bag then crush until its powder-like.
  3. Mix the crushed fine powder eggshells with the dog food for extra calcium that aid in fortifying your pet’s bones and teeth.

15. Eggshells as Garden Mulch

After using eggs for meals and food preparations, bring the eggshells out and spread them all over your garden. The slowly decomposing eggshells will help supply air to the soil and provide calcium as well.

Note: The finer the eggshells are crushed, the faster they will decompose.

Check this video for more ideas on why and how to use eggshells in the garden:

There you have it smart green thumbs! Practical ideas on how to use eggshells in the garden.

I hope I’ve also enlightened you on why you should use eggshells in the garden and how to cut back on your gardening expense. Isn’t it surprising that what we need for the garden are accessible at home?

How do you use your eggshells in the garden? I’d be delighted to find out about your own ideas in the comments section below.

Planning a vegetable garden for a fresh and free food source? Check these 3 common gardening mistakes first to avoid them and avoid wasting time, effort, and money.


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Editor’s Note: This post has been updated for quality and relevancy.

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