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I don’t throw away eggshells anymore. Instead, I keep them aside because they’ve become part of one of my favorite little gardening tricks.

Those leftover shells make surprisingly good seed starters. Instead of buying plastic trays or special containers, you can use something you already have in the kitchen. Eggshells are biodegradable, easy to work with, and when they eventually break down in the soil, they add a small boost of calcium to the garden.

If you’re starting seeds indoors in early spring, this is an easy way to reuse something that would normally get thrown away.

Why Eggshell Seed Starters Work So Well

There are a few reasons I keep a bowl of eggshells on the counter during planting season.

They reduce waste.
Using eggshells means fewer disposable seed trays or plastic pots.

They break down naturally.
When you transplant seedlings into the garden, the shell can go right into the soil, where it will slowly decompose.

They cost nothing.
If you cook with eggs regularly, you already have everything you need.

What You’ll Need

You only need a few simple supplies to get started.

A dozen eggshell halves
A small needle or sharp pin (for drainage holes)
Seed-starting soil or light potting mix
Seeds such as basil, oregano, lettuce, or herbs
A spoon
An egg carton to hold the shells upright

How I Make Eggshell Seed Starters

Save and Crack the Eggshells

When cracking eggs for cooking, try to remove only the top portion so the bottom half of the shell stays mostly intact. That bottom piece becomes your little planting container.

Pour the eggs into a bowl as usual and set the shells aside.

Rinse and Dry the Shells

Give each shell a quick rinse to remove any leftover egg. This helps prevent odors and keeps mold from forming while your seedlings are growing.

Let the shells air dry before filling them.

Add a Drainage Hole

Using a small needle or pin, gently poke a tiny hole in the bottom of each shell. This step is important because it allows excess water to drain out rather than sit around the roots.

Be gentle so the shell doesn’t crack.

Fill with Soil

Spoon seed-starting soil into each shell until it’s about three-quarters full. Leave a little space at the top so watering is easier.

Try not to pack the soil too tightly. Seedlings grow better when the soil stays loose.

Plant the Seeds

Place your seeds on top of the soil according to the depth instructions on the packet. Some seeds need to be lightly covered with soil, while others just need to be pressed gently into the surface.

Small herbs like basil or oregano are perfect for eggshell containers.

Set Them in an Egg Carton

Once planted, place the shells back into an empty egg carton. The carton keeps everything upright and makes it easy to move the seedlings around if needed.

When It’s Time to Transplant

Once the seedlings grow a few sets of leaves and are strong enough to handle, they’re ready to move into the garden or larger pots.

One of the best parts of using eggshells is that you can plant them directly in the soil. Simply give the shell a gentle squeeze to crack it slightly so roots can grow through, then place the whole thing in the ground.

The shell will gradually break down while your plant continues to grow.