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Our friend Elliot thought we should do an episode about composting... so we did! Learn all about how you can turn certain types of trash into nutrient packed soil you can use in the garden!

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Do you remember when we were talking about recycling, and how we can turn things, like old paper, metal, or plastic, into new things? Well, did you know that we can also recycle plants? It's true, and you do it by turning stuff like dead leaves, apple cores, and kitchen scraps into compost!

Compost is a special kind of dirt that you can make by setting aside certain kinds of trash, and letting it rot. It might seem kind of yucky to keep a bunch of old banana peels and dead leaves around, but this waste will eventually turn to compost, which you can use in your garden to grow flowers or vegetables or anything you want. So how do we get from what we might consider trash to yummy vegetables?

Have you ever been out on a walk and seen an apple core that someone dropped on the ground? After a while it gets all brown and mushy and kind of slimy, and eventually it seems to sort of disappear. But, it doesn't just go away, it decomposes. When something decomposes, it breaks down into teeny tiny pieces, and decomposing is helped along by a group of living things called decomposers.

That's a pretty great name, because decomposers get their energy by breaking down things that were once alive. That apple core, it was once part of an apple tree, and that bread crust from your sandwich, it was made from ground up parts of the wheat plant. Decomposers use these bits of once living things as their own food. They basically eat our garbage.

Decomposers include things like mushrooms that grow on rotting logs, and insects and worms that eat the scrapes that come from that sandwich that you didn't finish. They even include tiny little things too small for us to see.

These guys might seem like they have a pretty gross job, but it's a really important one, because decomposers turn those leftover parts of living things into compost. And compost is important, because it's full of nutrients.Your body uses nutrients from the food you eat to build a healthy body, and plants need nutrients too. They use nutrients to grow taller, and maybe sprout some flowers, and make all of the plant parts that we eat as fruits and vegetables. So, without decomposers, plants wouldn't be able to get the nutrients that they need. 

Now, let's see if we can't put some decomposers to work to make some compost. Many people who make compost have a big bin in their yard somewhere, but if you don't have a yard you can still make compost in a small container, like a special compost bucket or even an empty soda bottle. No matter what you use, to get good compost you need to follow a kind of a recipe, just like cooks do in the kitchen.

Let's start by looking at our bin. The bin can be made of metal, wood, or plastic, but it should have holes in it so that air can get in and out. Air is an important ingredient in making good compost, because many decomposers like insects and worms need air to breath, just like you and I do.

Next, we need our waste, and we should group it into two main colors. That's right, colors! The waste you use to compost is generally either green or brown. Green waste includes things like kitchen scrapes, but we can't use all the stuff that we throw out in the kitchen. Meat and cheese, for example, can attract animals that might dig through our compost. So, stick to fruit an veggie scrapes, which is what we call the green stuff. Brown waste is usually, you guessed it, brown. This kind of waste includes dead leaves, straw, and saw dust. We need about two times as much brown waste as green waste. Put the green and brown waste into your bin in layers, and add some water to make it moist.

Now all we need are our decomposers. If your bin is outside, you can just wait. Decomposers like insects and worms will move right in, and start munching on your waste. If you're composting inside, you can add some earthworms to your composting bin, or even find special red worms that are really good at making compost.

Oh, and I almost forgot, we need patience, because composting takes time. Depending on how big your bin is, it can take months for decomposers to do their jobs and break down all of the waste. If you want to help them out a little bit, give your compost pile a little stir, or turn it over with a shovel.

And while you're waiting, you can do some observing. If you watch your compost pile over time, you'll see some pretty cool things. You might see some mushrooms start to grow on it, and you should see a whole lot of different insects and worms. If they're doing their job well, and if you've done a good job adding your ingredients, the compost won't even smell bad.

Once the wait is over, and your compost is ready, it'll look like dirt, but compost is more than just plain old dirt because it's packed full of nutrients that the waste still had inside of it. So, in a way, compost is a way you can recycle plants into new plants. It let's you turn garbage into greenery.

Thanks for joining us on SciShow Kids, and special thanks to our friend, Elliot from Portland, Oregon, who gave us the idea for this video. Do you have a question for us? Let us know in the comments below, or email us at, and we'll see you next time.