Your Leftover Eggshells Are the Easiest Fertilizer Hack for Your Garden

Because kitchen trash is garden treasure.

Our editors and experts handpick every product we feature. We may earn a commission from your purchases.

It’s no secret that your plants need vital minerals to survive. Typically, garden fertilizers contain nitrogen, phosphorus and potassium to promote plant health and growth. But did you know that plants, like humans, can also benefit from calcium?

There are lots of different ways to infuse your garden soil with calcium, and this week, TikToker GardenShare (@gardenshare) reiterated one of our favorites. To get started, all you need is a bunch of eggshells, so hang onto those kitchen scraps, then read on to learn how to properly amend your soil with them.

Why Calcium Is Good for Plants

Three Fresh sprouts in various growing stages shown growing on a tree in the morning lightArtRachen01/Getty Images

While you’re hoarding your eggshells, let’s discuss why calcium is so helpful in your garden. Calcium provides a number of services to your plant, including:

  • Strengthening cell walls
  • Maintaining pH levels
  • Improving water penetration
  • Increasing resistance to disease

How to Know If Your Plant Is Calcium-Deficient

There are four main signs of calcium deficiency in plants. To determine if your plants need more calcium, look out for:

  • Curling leaves (also known as “parachute leaves”)
  • Brown or yellow spots on leaves
  • Rot (either above ground or at the roots)
  • Slow growth

When in doubt, test your soil to know which specific amendments it needs.

How You Can Add Calcium to Your Soil with Eggshells

Now that you understand a bit about the role of calcium in plant growth, it’s time to get back to those eggshells! In the below video, GardenShare creates a soil amendment from eggshells to add to their garden.

@gardenshare Homemade Eggshell Calcium Fertilizer Nutrient Soil. #homemade #organicfertilizer #gardeningtips #diygarden #nutrientsoil #eggshefertilizer #gardeninghacks #sustainability #ecofriendly #gardeningcommunity #plantlovers #soilhealth #gardeninspiration #greenthumb #urbanfarming ♬ original sound – GardenShare

In the video, the Tiktoker first spreads their saved eggshells out evenly on a baking sheet and places them in the sun to dry. Once the shells are dry, they crush them up. You can use a piece of wood, a rolling pin or a meat hammer to do this yourself.

Then, once the shells are broken into dime-sized pieces, GardenShare pours them into a blender—you can also use a food processor. When the shells have been pulverized into a fine powder consistency, they transfer the powder into a resealable plastic bag for storage. From there, they sprinkle the eggshell powder into potting soil and mix it evenly.

Van Van Cleave
Van Van Cleave (they/them) is a California-based journalist, environmentalist, and artist. A graduate of Brown and Oxford Universities, they specialize in environmental news coverage and sustainable home and garden solutions. When they're not writing, they are typically tending to their plants or experimenting with home design trends.