One of the great benefits of home composting is reducing your food waste.
It can be truly satisfying knowing that a corn husk, an asparagus stalk, or a fish skin is contributing to the soil that will help grow new, fresh plants.
You’re helping the environment and creating a more sustainable, efficient home.
Certainly, one of the most common food waste items for any home is the egg shell. After a family breakfast, you might have six to eight discarded shells.
After Easter weekend, you might have two dozen! It’s a ridiculous waste just to chuck them into the waste bin.
There’s no doubt that egg shells are a great amendment to your compost. Still, can you have too many egg shells in your compost?
Let’s look at the benefits and challenges of incorporating egg shells into our compost pile.
Understanding how egg shells break down and what particular benefits they provide will help us determine if you can use too many.
Benefits of Egg Shells in Compost
To begin, you should understand why egg shells provide important biological material to your compost pile.
As we all know, eggs – like all raw dairy products – are extremely high in calcium. This extends to their shells.
When you add eggshells to your pile, you will greatly boost the calcium content of the resulting compost.
How does calcium aid plant growth? It is the building block of cell walls.
In fact, calcium carbonate makes the shell strong enough to protect the egg itself.
So, the end benefit of adding egg shells to compost is stronger cellular durability in plants.
This means faster-growing and hardier plants. This will also prevent much premature rotting on fruits and blossoms.
Even if an egg shell has not fully broken down, it can still provide wonderful benefits in your garden. Crushed or partially-composted shells in your compost can deter pests.
Slugs and snails receive minuscule abrasions when crawling across these shells, which in turn causes them to dehydrate and perish.
How Egg Shells Decompose
When you add old produce or yard waste to your compost, you can expect to see it break down and incorporate itself fairly quickly.
You can’t say the same thing for egg shells. They do not break down easily when fully intact.
A whole egg shell will barely affect soil composition in the short term. After a year or so, it will eventually decompose.
As noted earlier, it will increase the calcium content.
That egg shell will also increase the potassium content and raise the pH of compost slightly, making it less acidic.
Challenges with Composting Egg Shells
Egg shells are significantly tougher than most other food waste.
They break down slower and can remain intact within compost for a long time. Ironically, the very benefit of adding an egg-shell to your compost – its high calcium quotient – is what makes it resistant to quick composting.
As noted, this doesn’t mean they are useless or detrimental in composting.
Whole egg shells will reduce pest damage to plants, and given some time, they will fully break down. The chemical benefit of including them in compost might be delayed, however.
Unfortunately, you might not see that benefit at all if you end up dredging up the shells when you pull your plants out at season’s end.
So how do we mitigate these challenges and compost our egg shells effectively?
Mitigating the Challenges of Composting Egg Shells
Since the challenges involving composting egg shells are mostly related to the time it takes for them to break down, the best thing you can do to mitigate this is to crush them well.
Rinse the egg shells and let them sit for a couple of days to dry out thoroughly.
Then, run them through a food processor or a coffee grinder.
You can also grind them down to a granular powder with a mortar and pestle.
This powder will incorporate into your compost much quicker.
Within a couple of days, your compost will see the calcium and potassium benefit of the egg shells.
Alternately, you can leech the calcium from your egg shells by boiling them, then letting the water and shells sit overnight.
After that, just discard the shells and add the calcium-rich water to your compost.
Your soil will receive all the benefits.
Is There Such a Thing as Too Many Egg Shells?
In the end, you probably can’t add too many eggshells to your compost.
If you grind them down, they will soon impart calcium and potassium to your compost.
If you leave the shells partly crushed or entirely whole, it will take a while for them to break down.
Even in this circumstance, though, they’ll provide the benefit of repelling pests in your garden.
The only biological concern to adding a lot of egg shells to your compost is the pH.
If you are planting something that requires high-acidity soil – such as sweet potatoes or blueberries – you should be aware of your compost’s pH.
While egg shells will not severely increase the pH of compost, they will definitely affect it in large quantities.
You can mitigate any potential change with more acidic material like wood ash or coffee grounds. As always, you should also regularly turn over your compost.
Once you weigh the benefits and concerns of adding egg shells to compost, it’s pretty clear that they are a net positive.
If you prepare them properly and monitor their effect on the soil, you can’t really have too many egg shells in your compost.
The important steps to take are:
- Grind the dry egg shells into a granular powder to ensure that they break down into the compost quickly.
- Check the pH of your compost and planting soil carefully. If the inclusion of egg shells increases your soil’s acidity too much, add acidic items to off-set the effect.
With those two mitigating actions, you can stop throwing your egg shells into the trash and start using them productively.
Also, don’t worry. Those Easter-painted shells will not produce multicolored tomatoes!
Adding egg shells to your compost will enrich it with added calcium and repel garden pests.
However, considering how long they take to break down, you have to ask: Can you have too many egg shells in your compost?