Eggshells for Plants: How to Use Leftover Eggshells for Your Plants and Garden

We're always trying to find new ways to deal with our food waste. Sometimes, that's transforming it into recipes like potato skin chips and candied lemon peels. Other times, that's upcycling it into beauty products. But how about using eggshells for plants—are they actually beneficial for your indoor jungle?

While eggshells are compostable and can be added to your kitchen countertop bin or backyard compost pile, using eggshells for plants is also beneficial. They provide important minerals—namely calcium carbonate, potassium, and phosphorus—that can be absorbed by your plant’s roots after breaking down.

The catch? Most people use their eggshells incorrectly, which prevents them from giving plants a calcium boost.

Are Eggshells Beneficial for Plants?

The main issue with using eggshells for plants is how long it takes for them to actually decompose. With how slow the process is, it could take up to a year before the calcium is absorbed—aka no instant fix for plants that need some TLC.

Instead of working hunks of eggshells into your garden or potted plants, grind them up. According to a study from Alabama Cooperative Extension, finely-ground eggshells that resemble a powder are more effective than coarsely-ground eggshells that are crushed by hand.

In the study, the finely-ground eggshells were found to work just as well as pure calcium. Meanwhile, the coarsely-ground eggshells were said to be "not much better" than using no eggshells at all. Learn how to properly use eggshells in your plants and garden below.

How to Use Eggshells to Give Your Plants a Boost

If you want to provide your plants with a natural source of nutrition—and reduce food waste in the process—put your leftover eggshells to good use. There are two ways you can go about it.

1. Grind Up the Eggshells

The first way you can use eggshells in your houseplants is to grind them up. First, clean the eggshells and allow them to fully dry. Once dry, add them to a coffee grinder or food processor and grind until you have a fine powder.

Once you have a fine powder, how you "feed" your plants is key. According to Khoa Hoang, Brightly’s product designer and resident plant expert, fertilization starts at the roots of your plants. Because of that, simply sprinkling eggshells on the top of the soil in hopes that the nutrients trickle down won't cut it. Instead, he recommends working the eggshell powder into the soil.

2. Make Eggshell Tea

You've probably heard of making a compost tea for your plants in order to give them a nutritional boost. But if you don't have a way to grind up your eggshells, you can also make an eggshell tea that can be easily absorbed by your houseplants.

Creating an eggshell tea is simple. First, rinse and dry your eggshells. Once dry, boil some water. As you're waiting for the water to heat up, crumble the eggshells with your hands.

Once the water is boiling, remove the pot from the heat and add the crumbled eggshells. Let the mixture steep, just like you would your favorite tea. Once the water reaches room temperature, strain out the eggshells and add them to your compost bin. You can now use the calcium-rich tea to water your plants.