Which Vegetables and Flowers Shouldn’t Be Started in Eggshells?

I remember having big dreams of starting my own seedlings and saving a ton of money on our garden. While it can be a rewarding and budget-friendly task, the older I get, the more I lean toward just buying started plants. But if you’re feeling ambitious and want to try growing from seed, planting in eggshells is a fun and eco-friendly way to get started.

That said, not every plant loves being tucked into a tiny eggshell pot. Here’s what to know before you crack into seed starting.

Why Use Eggshells for Seed Starting?

Eggshells make adorable little seed starters, and they’re a great way to reuse something you’d normally toss out. For backyard chicken keepers and gardeners alike, it feels good to repurpose natural materials and cut down on plastic waste. Plus, eggshells break down in the soil over time and offer a small calcium boost to your garden, which can support healthy plant growth.

To prepare eggshell seed starters:

• Crack eggs near the top to keep the shell mostly intact

• Rinse out the inside and let them dry

• Poke a small drainage hole in the bottom

• Place shells back in the carton for stability

• Fill with seed-starting mix and plant your seeds

Eggshells are especially fun for kids or anyone looking for a hands-on gardening project. Just remember, they’re small, so they’re best suited for plants with compact root systems or those that grow quickly and can be transplanted early.

Fast Growers and Deep Rooters Need More Room

Some plants just aren’t a good match for eggshell seed starting, either because they grow quickly or send roots deep into the soil. Eggshells are eco-friendly and effective, but their small size can limit root development and cause more harm than good for certain crops.

Fast-growing vegetables like lettuce and radishes often do best when sown directly into the garden or larger containers. I personally love planting big pots of lettuce on our deck. It looks beautiful and makes picking supper a breeze!

You’ll want to skip eggshells for these plants with large or deep root systems:

• Lettuce and radishes – Fast growers that quickly outpace the small space

• Tomatoes, cucumbers and squash – Develop sprawling root systems

• Carrots, beets and parsnips – Need deep soil for long, healthy taproots

  
  

Trying to grow these in eggshells can lead to stunted growth, crowded or twisted roots and transplant shock that slows them down once they hit the garden. In the case of root veggies, it may even lead to misshapen or poorly developed produce.

If you’re growing any of these crops, give them a better start with deeper seed trays, small pots or direct sowing into the ground. They’ll thank you for the extra space.

Heavy Feeders Need More Than Calcium

Additionally, corn, peppers and similar plants are known as “heavy feeders,” meaning they need a lot of nutrients to grow. While eggshells offer calcium, they can’t come close to meeting the early nutrient demands of these plants. That’s especially true during germination and the first few weeks of growth, when a solid nutritional foundation sets the tone for the entire growing season.

If you’re starting heavy feeders, opt for a high-quality potting mix with added compost or natural fertilizers. Use larger containers or seed trays that allow the roots to expand and access those nutrients. You’ll set your plants up for better growth, higher yields and less transplant shock down the line.

And if you raise chickens, this is a great spot to use composted chicken manure to enrich your mix. Just make sure it’s fully composted and aged, as fresh manure is too strong for seedlings and can burn them.

Acid-Loving Plants and Eggshells Don’t Mix

Soil pH plays also plays a big role in whether your plants thrive or struggle. Some plants, like blueberries, and azaleas, prefer more acidic soil to help them absorb the nutrients they need. Eggshells, on the other hand, are naturally alkaline. When used as seed-starting containers for acid-loving plants, they can raise the pH of the soil just enough to cause problems.

If the pH isn’t right, these plants may struggle with nutrient uptake, which can show up as yellowing leaves, weak stems and stunted growth. In short, it’s not worth the risk.

To give these types of plants a good start, skip the eggshells and choose a seed-starting mix designed for acid-loving plants. You’ll set them up for healthier growth and fewer nutrient issues from the beginning.

Tiny Seeds Can Be Tricky in Eggshells

Seeds from flowers like petunias and snapdragons are so small that spacing them in an eggshell is tough. If you can manage it, it’s doable, but it’s much easier with seed trays that have more space and separation.

So… Should You Start Seeds in Eggshells?

Starting seeds in eggshells can be a fun, sustainable option. I used to love doing it when our kids were little. But now? I’ll admit, I skip the hardening-off process and head to the garden center for transplants. No shame in that!

Whether you go DIY or buy your seedlings ready to plant, one thing’s for sure, nothing beats the flavor of homegrown produce. Our garden is right next to the chicken run, and the girls would agree… gardening season is our favorite season!

Until next time,

-The Wing Lady