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Sent in by:
Taylor of Longview, TX

Huh? Compost? Oh yeah rotting vegetation.

Materials Needed

  • 3 two-liter soda bottles - let's call them A, B and C
  • one bottle cap
  • scissors
  • old vegetable or yard scraps (grass, lettuce, leaves)
  • soil w/ bacteria and organisms
  • water
  • tape
  • thumb tack



  1. Remove the labels from the soda bottles and mark them A, B, and C with your marker.
  2. Bottle A: Cut the top off 2-3 centimeters above the top curve and cut the bottom off 2-3 cm below the bottom curve.
  3. Bottle B: Cut the bottom off 2-3 cm above the bottom curve.
  4. Bottle C: Cut the top off 2-3 cm below the top curve.
  5. Punch a lot of holes in one of the bottle caps with the thumbtack and screw it on bottle B.
  6. Invert bottle B into bottle C. Tape them together.
  7. Tape bottle A to bottle B. It doesn't matter if it's inside or outside of the other bottle.
  8. Fill them with all the yucky vegetable and fruit scraps. Don't add any meat or dairy products. Those will only make it smell bad.
  9. Be sure to put some soil in there because it contains bacteria, organisms, and fungi that will turn the mixture to dirt. Add enough water to moisten the ingredients.
  10. Take the top that you cut off bottle A and tape it to the top of the bottle structure. Screw on the cap. Shake it all up.
  11. Use a pin to poke air holes in the compost column. Air will help the ingredients decompose.
  12. After 2-3 months you'll end up with nice, rich dirt that you can feed to your houseplants. Yum.

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Some of your Results

Graczzan, age 9 of San Antonio wrote:
It worked really well I have a big yard so we made a pile in are yard the pile is huge. The only problem is my dogs every time we putin something my dog eats it YUCKKKKKKKKKK!

Aubrey, age 12 of Mesa, AL wrote:
It was realy cool. We put in our garden belive it or not it realy woorked thoose were the best bloosms ever.

Lindsey, age 8 of AK wrote:
Well, I think it helped the enviorment, and of course, it was alot of fun, but it kind of smelled. I put it outside when I was done. Whoa, it drove my older sister Mc'Kenzie nuts with the smell. She is eighteen.

Gregory of WA wrote:
I tried this but so far it hasn't worked. When I tried this I didn't use grass in it. I think it needs sun too and in Seattle there isn't much!

Andrea, age 12 of Farmington Hills wrote:
Its a great idea! I started using a big one in my yard and my school has some!

Ashley A., age 11 of Vancouver, WA wrote:
When I did the compost thing I thought it wouldn't work, but when I did, it it really worked. It was kind of smelly.

Lillian C., age 13 of Chicago, IL wrote:
Four weeks after I started my compost pile I used it in my garden. It worked great! My parents thought it was such a great idea that they are gonna make a big compost pile in our back yard!!!

Ashley A., age 11 of Vancouver, WA wrote:
I am doing the compost with the soda bottles. I don't know if it is working but I still have about a week left. I put tomatoes, banana peels, zuchini, soil and grass clippings in it.

Justin L., age 11 of Keizer, OR wrote:
When I made it I thought it wouldent work. A month later it made soil! Now the plant I put the soil in is looking a lot better!!

Kaylee W., age 16 of Pollock, AR wrote:
I didn't have three 2 liter soda bottles so I just used paper cups. I used three paper cups. One small, and two larges. Stick the bottom of the large one into the small one, and put the rim of the other large one on top of the other large. Tape them together. Cut the top off of the cup on the top. Put all your stuff in that hole. Then seal it with plastic wrap. Put a rubber band over it so no air gets in.

not yet implemented