seed starting in egg cartons27 February, 2012

It’s finally time to start seeds again! After months of winter garden dreaming, action at last!

First come the onions. We’re planting a bunch this year, maybe not enough to grow all our own, but enough to make a dent. And we start just about every meal with sautéing onions in olive oil, so we’re starting 150 onion seeds, and we’ll see where that takes us.

While we’ve got some of those black plastic trays you see at garden stores for seed starting, we don’t have enough of them for 150 onions and everything else we’ll be starting later on. So we got creative.

Here’s what we did:

1) Got a bunch of egg cartons (Thanks, John!) and punched holes in the bottom, for drainage.

2) Cut out a panel from the lid on three sides, so we have a flap of sorts on top, while stapling the original lid closed (we tried glue, but staples were easier). This means we can fill the cartons with soil all the way to the top, giving our little seedlings extra room to stretch their roots.

3) Filled the bottom half of the cartons with potting soil, and then put in enough seed starting medium on top for the seedlings to emerge into.

4) Put in our seeds, one future-plant per cell. We’re trying some yellow storage onions, red salad onions, white sweet onions, and cippolinis this year.

5) Closed the flap on top to keep in moisture while the seeds are germinating. Once they’re up, we’ll rip off those top panels and stick the cartons under lights to grow until the garden is ready for them.

We consider gardening, at least at our skill and experience level, to be one experiment after another. We’ve always got high hopes. We’ll let you know how it goes.


Update 8/3/12: We had a lot of trouble keeping the soil in the paper egg cartons moist, because the paper just wicks away the water in the dirt. But it all stayed wet enough for some very colorful mold to grow all over the wet paper. Neither the moister level nor the mold was an issue with the one styrofoam egg carton we used, but then it was also not compostable at the end of the season. We are contemplating other systems to try next year.



  • I’m fascinated by the seeding soil on top of potting soil experiment. Please keep us updated. Really watch the moisture with this setup. Every time I try bigger containers for seed starting I struggle with this aspect!

    CJA27 February, 2012 at 11:16 pm

  • Clever! I repeatedly find egg cartons to be too small, but this solves this problem!

    Nicola28 February, 2012 at 3:18 pm

  • yeah…re: moisture — too little can be a problem because the “soft cardboard” absorbs and then transmits OUT…too much can rot out the bottoms…still, since you guys do pay such close attention to details like this, these could be a great idea — but probably single use?? so, should I go back to saving them for you?? inquiring minds, you know…jaa

    johnA29 February, 2012 at 8:54 am

  • JohnA – We’ll let you know how it goes this season before you need to save us any more. We’ve used newspaper pots before (same moisture-wicking paper issues), but only with larger seedlings. And we’re curious if we can sterilize them for reuse in the oven the way you can soil… Like we said, who knows. We’ll keep you posted.

    A29 February, 2012 at 9:50 am

  • I have used egg cartons in the past to start seeds as well, only I just used the bottom of the carton. I set the carton in a shallow dish and placed water in the dish to help aid in keeping them moist. The carton will soak up as much water as needed to stay damp.

    Dawn Herman1 June, 2012 at 11:43 pm

  • Dawn – That’s helpful. We had so-so germination in the cartons, which might have to do with moisture. If we do this again next year, we’ll try the water dish trick.

    A2 June, 2012 at 8:00 am

  • I just saw this on Pintrist. We have a garden that we started last year and a neighbor gave us some onions to plant and they were really pretty growing, and yummy at harvest. Where did you purchase the cool ones you mentioned?

    Elizabeth5 January, 2013 at 8:15 pm

  • Elizabeth – We bought our seeds from Seed Savers, which is an awesome non-profit you can feel good giving your money to, and they have an amazing collection of heirloom varieties. Check them out here:

    K6 January, 2013 at 12:40 pm

  • good

    Aldo16 February, 2013 at 11:00 am

  • A horticulturist gave me a great tip for white mold prevention. Add 3 tablespoons of white vinegar to 1 cup of water in a spray bottle. Spray on the mold whenever you see some coming. She said this mixture is also a great bug repellant. Spray on outdoor table & furniture before your next outdoor gathering. I will be trying both of these ideas this year. Already made the mixture in a spray bottle from a dollar store. Look out, mold & bugs!

    Dana Tock18 March, 2013 at 9:23 am

  • Try putting paper carton inside foam carton

    oleth23 March, 2013 at 6:45 am

  • I set the paper cartons inside the foam cartons, that way I can just lift out the paper part and plant right into my pots and garden. This is my first attempt but after two weeks in my windowsill, there’s been no mold growth and lots of little sprouts.

    Sabrina25 March, 2013 at 7:32 pm

  • For the cardboard carton issue – how did you prepare your soil before you put it into the carton?

    Pre-moistening the soil before putting it in could help reduce the amount of water that the cardboard wants to suck up. If you just put dry soil in, the water will not be able to penetrate it fully and will slide off and run to the sides, hence the cardboard sucking up most of it and becoming moldy.

    I am going to try this method for seed starting. :)

    Hannah6 April, 2013 at 12:27 pm

  • I want to try egg cartons for my seedlings, too. Would mod podge or another paintable sealant help with the mold and absorption?

    Alicia10 April, 2013 at 1:14 pm

  • Has anyone tried toilet rolls? I’m keen when it starts getting colder (June and July) to prep my seeds for September (spring) planting.

    Justine4 May, 2013 at 2:03 am

  • Has anyone tried plastic egg cartons!

    Cathy10 May, 2013 at 11:16 pm

  • I have the cardboard carton method going good. I put the seed starter soil in, wet it well with a spray bottle so the soil doesnt spill then put the seeds in (peas) and kept it moist with a spray bottle every day. I have also tried to put the egg carton in a tray with some water in the tray but the carton fell apart. I had also tried the plastic egg cartons with holes in bottom and found that works too, but unfortunately you can’t plant plastic but you can plant the cardboard. Just cut out each little cup!

    kathyann19 May, 2013 at 1:05 am

  • Oh, and I didn’t cover the cardboard, just put plastic film on lightly to keep seeds moist!

    kathyanne19 May, 2013 at 1:06 am

  • I use egg cartons to start some of my garden seeds as well. The only thing I had to watch for was NOT moving them after I watered them as they can get a little soggy.

    James Mann20 May, 2013 at 4:36 am

  • I put mine on trays that I found at garage sales. I also use baking sheets that I find there. You can then move them and adjust the water by watering from the bottom and misting at the top!!

    kathyanne20 May, 2013 at 1:40 pm

  • Oh, and another thing I do. I WET the cardboard egg carton so it is moist when putting in the soil, then WET the soil before planting the seed.

    kathyanne20 May, 2013 at 1:42 pm

  • We are about to start a series on learning more about plants and helping the environment. This will be perfect! Thank you!

    Sheila @ Pennies of Time27 May, 2013 at 7:18 am

  • I put anything I plant in my classroom in a sprouting chamber for a couple of days. It is simply a Rubbermaid tub with the lid closed. This holds the moisture in and allows it to moisten all of the seeds and soil. Just be sure to remove them before they emerge and stretch out looking for light.

    T. Willis6 July, 2013 at 5:04 am

  • I like the variation of the egg carton idea. I have been using toilet paper rolls in cafeteria cups. I do like the plastic cafeteria cups. It allows each child to have his/her own plant. I put each students number on the cup and on the toilet paper roll.

    T. Willis6 July, 2013 at 5:06 am

  • I do this with a little less soil and keep the lid to cover on those cold frosty nights mine are our doors like little hot houses and they grow well and stay moist than rrip the base off and plant in the garen work well

    tuna9 August, 2013 at 1:56 am

  • You can use TP rolls. You need to bake them in the oven (I wouldn’t try this in a toaster oven as the elements are close in and could set the cardboard on fire.) first to kill any bacteria that might have transferred onto the cardboard. (lowest heat setting) I stood mine up in a long tray type planter pot, filled them with my compost and planted my seeds. I needed extra rolls so cut paper towel rolls down and used those too. All my seeds did fantastic although I did have a small amount of mold in between the rolls close to the bottom where they stayed wet, the plants did great and were super easy to transplant into the garden.

    Jan12 August, 2013 at 7:54 pm

  • Why not plant the seeds inside empty egg shells and set them down inside the carton. When they are ready for planting just puck up and set in the ground.

    ana25 January, 2014 at 5:35 am

  • Why not take an empty eggshell.and place your seeds in it ti start growing. Once it is ready for planting just remove the individual eggshell and place it in the ground.

    ana25 January, 2014 at 5:41 am

  • I use toilet paper and paper towel rolls to make seed pots as well as newspaper and cereal box cardboard. I put the seed pots in plastic silverware/drawer trays that I found at the $1 store. Works great and the trays are easy to clean at the end of the season. Just pop the seed pots in the ground when you plant and you have the cardboard collar already on the plant. I love to garden!

    Amy4 February, 2014 at 5:49 pm

  • i did the same thing as the person above mentioned. toilet paper rolls and paper towel rolls cut to the same length. my husband had purchased some organic salad mix at costco that came in a deep plastic container – the perfect size for the tubes. i nestled as many as i could inside that container and filled with seed starting mix. i did this for tomatoes as they like a longer pot. when they got about 4 leaves i transplanted them into larger pots and then placed them in the greenhouse until ready to go into the ground. when i went to transplant them they had lovely roots growing through the cardboard, so no need to remove the tubes! i was delighted with the success of this idea and have new tubes all set up again to use for spring 2014!

    Pamela Pollock20 February, 2014 at 7:57 pm