My Little Composter + the Plant-Buddy




My daughter was playing around with a couple of empty CD-ROM containers and got them stuck together. Every time you buy a pack of CD or DVD discs to be burnt onto, you get another one of these crafty containers. If you are like me, you download an awful lot of junk, try out a lot of new software, and generally waste at least one of these per month. I should conduct a scientific study on where all those discs end up (probably in the recycle bin).

Once you get a couple of these lids stuck together, you can never get them apart again. They trap the air between them, creating a vacuum of sorts. I got to thinking that you could easily use one of these to pot a plant. And you could use two of these to pot a plant, with a water trap in the bottom. The reasoning for the lower chamber is to catch the excess water that leaks through the soil. In doing so, you will keep from over watering your plants. Also, you will see just how much you are over-watering them, as you will be able to see the water trapped below. That water should dry up. And if there is no indication of moisture in the bottom, it may be time to water your plant again! We will call this contraption the "plant buddy" on account that you should not over water and kill whatever you grow in it.

What soil shall we use? Many smart people are finding that you can compost your own materials and come out with better soil than the stuff you pay high dollar for at your local home stores. We won't need a lot of soil for our small pot. Composting is science. You need the right amounts of the right materials, in the right temperatures to come out with good stuff. You may not want a rotting garbage can of waste in your yard while you experiment. Hence, the "My Little Composter". A see-through container where you can compost your materials in small amounts. My kids took an interest in this project which made me think that this would make a great future science project.

We started with three containers of various sizes, and the matching inter-locking bottom pieces.

Step 1: Stick Your Lids Together, and Drill Some Holes

If your lids are all ready stuck together, don't push them any further together. You may cause some structural damage in doing so (a crack). You can use a drill to do this, or a small steak knife. I like working with steak knifes for this because the material is so soft. If you use a drill, use caution. This plastic will give way pretty quickly. You don't want to drill all the way through the bottom container, or you will leak water on the counter every time you water your plant.

Pushing your knife inward, make a series of small holes. This will allow the water to seep to the bottom of the soil, and make it's way into the bottom chamber where it will dry up.

Step 2: Push the Lids Together

If the lids weren't stuck together yet, now if your chance. Give them a good shove. This part is not rocket science.

Step 3: Clip Off the Extra Tab Thingies, and Add Soil.

With your knife, slice off the extra set of tabs. You could leave them, but cutting them off gives this silly project a nice clean appearance. People will think that you bought this. Heck, you should start making these and selling them door to door to little old ladies.

Next, add your soil and seeds. If you plan on keeping this soil moist for new seeds (germinating) why not also add an earthworm? He will appreciate the new home, and you can appreciate what he does to your soil. You might also catch a glimpse of him moving around since the sides are clear. Make sure you use distilled water for healthier plants. If you want to use tap water, let it sit in a jar for a couple of days to let the chemicals evaporate.

Any old soil might due, but wouldn't you rather use some freshly brewed composted materials? Let's get working on the composter next.

Step 4: Build Your Composter

There's not much to this design. I kept things simple. These CD containers usually have a tube running up the center which the CD's are slid onto. Your base will use that tube to keep your composter up in the air.

Your base could be made out of anything. I went into my garage looking for old coat hangers, but I found some old wire that I had kept from a political yard sign. That stiff wire is great for a multitude of projects such as this one. With some pliers and a hacksaw I was able to get exactly what I needed.

My base on this project is rather narrow, as I used a small container. Those containers that come with 100 or more CD/DVD's in them would make a nice little barrel composter. But the base would need to be a little wider to accommodate for the weight.

We will want to make a few more modifications. See the next step.

Step 5: Put Some Holes in Your Composter Tub

Your composter needs to breathe. Without air, some moisture, and heat, your composter won't decompose the stuff we put in it.

You will need to poke some holes in your tub. Not too big, we don't want the stuff falling through the holes. You might want to use the steak-knife technique here so that you can control the size of these holes.

Commercial grade composters sometimes have holes through the center too. So you could even drill some small holes through the dark plastic tube that centers this whole job.

Step 6: Mount the Composter, Draw Your Line

Now all you have to do is "mount" the composter, and draw a line through the middle. The line will serve as your half-way point. You want to fill this half full, and then flip it once a week. This will not produce a lot of compost (as you might guess), but you are making use of garbage, and having fun.

If you have a bunch of these containers, you might create a whole line up of little composting units. In doing so, you can experiment with different materials in small amounts and then move up to a trash can sized job once you have the process down.

Check out the WikiPedia page for more information about composting, and some useful links to help you along.

Composting on WikiPedia

Feel free to chime in with suggestions, comments, or other such goofy ideas.

-Steve Ballantyne



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    34 Discussions

    Gato Nipon

    5 years ago on Introduction

    this looks more like a germinator. I love the use of the disc case, excellent idea !!


    7 years ago on Step 6

    Does it give off stinky odor of the composting garbage?


    7 years ago on Introduction

    Brilliant idea! I just emptied one of these containers yesterday and will be making my mini-composter today. Some have mentioned adding worms to create "vermiculture". However, I wonder if the heat created inside a composting unit would result in some cooked worms. As I understand it, in order for composting to occur the temperature of the material must reach a minimum of 130 degrees Fahrenheit. So, it would appear to me that it's one or the other-vermiculture or composting. Any thoughts?

    If you built lots of them, you could put a rubber band across all of them and then have an arduino with a motor turn them however often you like!


    8 years ago on Introduction

    As for reusing the discs themselves?  We've always collected them from coworkers.  We glue the tops together so the data surfaces (shiny sides) are on the outside.  Then just string them on fishing line and hang in the garden to look pretty and keep birds out of certain areas.  Mostly just to look pretty.  Catches the sun very well!!  *lol*


    9 years ago on Step 6

    I'm thinking about adding worms to this... but still studying up on the subject, starting with the Wiki site you provided. Thanks!


    10 years ago on Introduction

    This is a fun idea, and a great way to re-use what normally goes in the trash (at least for those who aren't pack-rat/makers). But how many of these can you use in your CD-burning frenzy? What if you bought CD-RWs and re-used the disks? It sounds like a lot of the software you download may be expendable. Better yet, get an external (or add an internal) hard drive to your computer and skip the CDs altogether!

    7 replies

    Reply 10 years ago on Introduction

    Well, even over a period of time, we can collect these because they're cool and should have some kind of reuse-ability. I have several. Further, after burning my cd's or dvd's, I transfer those that I keep into albums. Mostly, I do the burning for other folks. (Wedding videos, etc.) I thought it was a great idea. Now I'm looking for a great idea for reusing the trashed disks themselves!


    Reply 9 years ago on Introduction

    Anything you need structural support for in that shape. I have seen crochet projects that use discs for the support in the bottom of a bag or something.


    Reply 9 years ago on Introduction

    Rewritable discs are stupid! You can only rewrite something so many times, because you are having to burn the platter flat before you can burn new data back into it. This is often called "formatting" and adds another 10 minutes to the process of writing new data. Some discs can be written 12 times, while others can be written up to 22. But in my experience, by the time you get to the fourth or fifth time the disc starts getting read errors. Also, the cost of re-writable discs far exceeds the cost of regular one-time discs. You are better off buying a larger pack of one-time writable discs and then recycling them when you are done with them. Also - I don't waste nearly the number of discs that I used to. I wrote this a couple years ago now and I no longer try a new version of Linux every other day. ;-)


    Reply 9 years ago on Introduction

    Well, I feel pretty stupid when I make a mistake or have a failed burn on a CD-R and can't do anything but toss it in the recycling bin. I can't recall needing to erase a CD-RW more than once, so I guess my needs are different than yours. Last time I bought some, a couple of years ago, the re-writables were a few cents apiece more. CDRs seem to be harder to get these days anyway.


    Reply 9 years ago on Introduction

    If you do mosaic, you could Destroy them, and then make pretty art out of the pieces. Or you could keep them intact and decorate with them. Or both!

    We use the no good disks to hang around in our fruit trees to help keep the birds away from the fruit. The slight movement and reflection seems to scare them off at least until We harvest the fruit.


    9 years ago on Introduction

    hey i gotta new idea thanks to this but its all mine jk its a great idear really i wouldve never thought of this and my mom wants a mini composter

    going with worms stack a couple more high, with holes in bottoms for worms to work up... have some sort of drain at bottom one for worm compost tea.....

    as for the disk, i'm guessing most dont end up recycled, but we can hope, my good idea.....tie them from string outside in my garden to keep out the birds and such....


    10 years ago on Introduction

    If you drill a small hole in the bottom of the "dirt container" in your planter, and slide a small piece of cotton through (an old bootlace works great!), it will act as a wick to keep the soil moist at all times, and if you put a small "refilling" hole in the side of the bottom container just below the level of the upper container inside, you can add water in the bottom easily to leach into the soil on top.