Starting Seeds Indoors Using Egg Cartons

Photo of egg carton with sprouts and title of article.

This post may contain affiliate links, read my full disclosure here.

There’s nothing like beating the winter blues by starting your garden seeds indoors. It may feel a bit overwhelming when first starting out, but you can actually use a lot of resources you already have in your home for containers to plant in. If you’re new to gardening please learn more about different gardening methods so that you know where to start. Everyone can garden in some way, whether you live in an apartment or on 50 acres. Starting seeds indoors with egg cartons is simple but there’s a few things you should know:

Can You Use Egg Cartons to Start Seeds?

Yes! Cardboard egg cartons are perfect for starting seeds! Look around your house and chances are you have at least one carton laying around. Cardboard is ideal because you can directly transplant them into the soil. Can you use plastic egg cartons to start seeds? You can… but preferably not. Plastic will inevitably leech chemicals into the soil and into the food you will eventually eat.

An egg carton filled with seed starter mix and ready to plant.
Start your seeds with resources you already have lying around your home.

Starting Seeds With Egg Cartons is Recycling

You already have these resources lying around. Instead of throwing them away they will decompose instead in your garden, thus adding nutrients to the soil and making transplanting your young sprouts very easy. Helping the environment does not happen all at once, but little things here an there can add up to something big.

Also check out:

Harvesting Mammoth Sunflowers

Preserving Eggs In Limewater

Should I Bring Home Baby Chicks This Year?

Inexpensive and Functional

Chances are you already have them lying around or you can ask your friends, family and neighbors if they have any that they’d be willing to give to you. Once your new plants are ready to transplant into new containers it will be very easy because each will have its own cardboard egg slot to hold the roots and soil together. You can also cut the lid of the egg carton off and put it underneath as a tray for catching soil or soaking up excess water. Egg cartons are easily portable and you can label them accordingly, especially when you’re planting multiple varieties of seeds.

A display showing how you can use the lid as a tray for underneath your seedlings.
Cut off the top lid and use as a tray underneath.

Best Seeds For Egg Cartons?

Most seeds could technically be started indoors, but many do better directly sowed into the ground. Some of the more common seeds started indoors are:

  • Tomatoes
  • Bell Peppers
  • Broccoli
  • Cabbage
  • Celery
  • Brussel Sprouts
  • Cauliflower
  • Eggplant
  • Asparagus
Photo of an egg carton with holes poked in the bottom for drainage.
Adding holes to the bottom of the carton will allow proper drainage.

How To Start Seeds In My Egg Cartons

Starting seeds can be a bit of a learning curve, make sure you know the ins and outs of seed starting before you begin.

When it comes to egg cartons, you’ll want to first (very important), use a pencil, pen or screwdriver to poke a hole or two at the bottom of every single egg slot in your cartons. You will want there to be some drainage.

Once you’ve poked your holes, add your seed starter mix or soil to each egg spot, filled as high as you can.

Check the seed packet for information on how deep to plant your seed. We use the eraser tip of a pencil to poke 1/2″-1″ holes for the seeds to be dropped into.

Cover with soil and gently pat it. Water, keeping them moist as they are under their light source.

How Many Seeds Per Egg Carton?

When it comes to how many seeds you should add to each egg carton slot, that is really up to you. It’s not recommended to use more than five, but really one or two is probably just fine. Unless the seeds are old or haven’t be stored in ideal temperatures so you’re expecting a lower rate of sprouting, that should work fine.

Zoomed in on a egg carton tray of tomato sprouts.
Sprouts with soon to be four leaves, shown after thinning took place.

Thinning Out Your Sprouts

Say you added three seeds to one egg slot and all three of those beautiful sprouts are growing and happy, but crowding each other. This is the worst part of seed starting for many people, but you have to thin them. Yes, this means you’ll have to choose which one lives, while the others are pulled. Try to remember that someday soon that one little sprout will be a full grown, producing plant. Some people do try to pull them gently and replant with some success if that’s something that interests you. Just keep in mind you may have mixed results.

When to Transplant Seedlings From Egg Cartons?

How long can seedlings stay in egg cartons? Typically when your sprouts have 3-4 leaves on them is when you should transplant into larger containers. Keep in mind that you should wait until it’s warm enough to plant outside, or until danger of frost is gone. You do have to “harden” them first though before you can put them outside full time. You can do this by putting them outside during the day and bringing them in at night. The idea is to introduce them to the intense heat of the sun little by little so they aren’t put into shock. Best to start with a few hours the first day, add another hour or two the second day etc. Once they’ve gotten used to 5+ hours of sun, you’re then ready to put them out full time.

Transplanting seedlings from egg cartons is easy. This is partly why these egg cartons are so perfect for this. Simply use scissors or a knife to cut them into sections and plant them into the soil. Water well and you’re all set.

Eighteen tomato sprouts growing on a sunny windowsill.
Eighteen tomato sprouts happily on their way. Once they get to 3-4 leaves they will be ready for the next step.

Can You Plant Egg Cartons In The Ground?

Yes, as long as they are cardboard, you can plant your hardened plants directly into the ground. Make sure that the danger of frost has passed in order to give those new plants have the best shot at healthy growth.

Also check out:

Lentil Sprouts For Chickens & Your Family, A Protein Packed Winter Treat

Grandma’s Beautiful Fall & Winter Potpourri

One Crock-Pot Cobbler Recipe For Whatever Fruit You’re Craving

Water Purifying Methods For Your Peace Of Mind)

Egg cartons with sprouts growing under a grow light indoors.
Enjoy the journey!

Happy planting, have fun!

Let us know how it goes for you, would love to hear from you!

Wishing you and your family all the best on your self reliance journey.

Herbs, Birds & the Bees logo.

Herbs, Birds & the Bees

Garden, Chickens, Bees & Homestead

Thoughts?