Thinning Seedlings for Better Yield: How and Why

Posted on Mar 15 2011 - 2:20am by Mike Lieberman

Since I’ve started my garden from scratch committed to eating off from my balcony more often, I am taking better care of the containers.

It’s been a few weeks and the seedlings are starting to grow, so now it’s time to thin them out. What that means is cutting out the extra ones.

When you planted your seeds, you likely scattered a few of them in the soil. Now that they’ve grown a little bit, there are a few of them that are really close to each other. You want to remove some of them. If you don’t they will be fighting for water, nutrients and space, which result in a crappy yield.

So where there are few really close, take a scissor and cut them at the soil line, leaving the healthiest looking one to continue growing. If you look at the back of your seed packet, you can see the recommended space between plants.

That’s the basics on how and why to thin your seedlings. You can also do this with the seedlings that you started indoors.

Any tips or tricks on thinning seedlings?

  • http://www.dirtandmartinis.com Nicky

    I use rock plant markers too!

  • Thepurplesquirrelcottage

    So simple but I think I needed to see this ;) my seedlings are so crowded..and it is sad..but being compost is a good job too I’ll whisper this to the ones that have to go ha!

  • http://www.facebook.com/rice.joseph Donald Calvin Joseph Rice

    good advice here and valuable. one thing you can do with the seedlings, particularly those for greens/lettuces, is throw them on your salad, too. sprouts from different other vegetables are also good.

    you can play around with the spacing recommended on the back of seed packages. most vegetables will stand a little bit closer planting than what you’ll see there. also, you might try growing things that have a shorter growing period, like radishes, in between your plants. because they grow quickly you can utilize your space more effectively. also, herbs like dill, because of the size, or root vegetables like carrots, because of the length of the taproot, can be planted alongside vegetables like lettuces with shorter roots, and there won’t be as much fighting for the same nutrients. a lot of that depends on proper soil amendment (layering) but it’s an option to think about since you have limited space.

    great blog, mike!

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    Mine are better though.

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    Someone also recommended using the seedlings on sandwiches or in salads.

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    Cool. Appreciate all the great advice.

  • Anonymous

    sometimes if the soil the seedlings are in is loose enough I can gently lift the ones I need to thin out and transplant them somewhere else.

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    That’s some pretty delicate hands you must have.

  • http://www.onegreentomato.wordpress.com Danielle

    I prefer to make seed tape which eliminates the need to thin seedlings and essentially, waste viable seeds and plants. I posted a tutorial on my blog a few weeks back, it’s in the February archives. :)

    If you still feel the need to thin, use those small baby scissors with the curved tip. They make it easier to get into small spaces near the plants and lessens your chances of accidentally snipping too many.

  • http://www.onegreentomato.wordpress.com Danielle

    My bad, the tutorial is in the March archives!

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    Very interesting. This would work great for long rows. The diameter of the containers are about 1′ or so, so not sure how many rows of TP I could fit in there. Love the idea!

  • http://nycgardening.blogspot.com Meemsnyc

    I have to thin out my lettuce seeds.

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    Glad I could remind you.

  • Chris

    my seedlings are growing pretty nice right now, they are probably about a week or so old. when do you normally thin them out? and if you do move some out, do you move them to the pot they will permanently stay in?

    thanks for the help!

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    I usually thin them when they are somewhere between 2-3 inches or so. Some people say that you can transplant them elsewhere, but I just snip em and use em in salads. Don’t have room to transplant them.

  • http://www.facebook.com/profile.php?id=1577687206 Barri Bomb

    hey mike, i need to do this, but not sure when. the seed packet says after first “true leaves” appear, but when is that? when they look more like plants and not sprouts?

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    Not sure what that means either. I think it means the second set of leaves that are growing. I usually do it when the sprouts are about 2-4″ or so.

  • http://twitter.com/Ark_Institute The Ark Institute

    If you are fortunate enough to be planting in-ground and have enough room to do so, it is possible to spread enough seed and eat the thinnings for quite some time, while allowing the larger plants to grow. Staging your plantings over a month or so (if weather permits this) will allow you to have more thinnings to eat throughout the early season too. 
    This is especially (or predominantly) intended for things like lettuces (instead of your pictured cilantro) where you can buy a good non-GMO mesclun mix of a variety of seed for just a few dollars and spread it widely. This packet of seed can plant a LARGE area, and will provide enough edible thinnings to keep you in healthy salads and greens for most of the season. These are the same salads that you can find in “fresh” prepackaged bags at the grocery store for $4 per bag (about 4 small servings). How economical is that?The same is also possible if you can’t go in-ground but if you do have more space than a balcony or fire escape. Some of my friends and customers have submitted stories and photos of using a cheap plastic baby pool on a rooftop in the city and using that as their “planter” or “container” –  That’s about 20 sf of “container” per pool, and easy to grow the shallow-growing, widely dispersed varieties like lettuces. 

  • http://www.UrbanOrganicGardener.com Mike Lieberman

    Good tip. Thanks for sharing!

  • Profshingie

    kunyepa kwako mface iwe ka!

  • http://www.facebook.com/profile.php?id=1117404222 Mary Ellen Schultz

    The first 2 green “leaves” are actually cotyledons. Think of a peanut, and how it splits into two pieces. These cotyledons are inside the seed, and come up when the seed sprouts to provide nourishment until the “true leaves” take over with photosynthesis.

  • surdas

    where you at man dont cut them down wait till its time to prick the spares out put them in jars, tins whatever and give them to passers by , supprise yourself

  • SallyBGood

    When my seedling grew too closely together, I just gently pulled one out & planted it further away. It never occurred to me to destroy it. I stuck a chopstick next to it, wiggled it a tad, and the seedling came right up. And yes, it grew where I replanted it.