Rotten apple, rotting leaves, but rotten plastic? Plastic just doesn’t rot like other materials, and heres an experiment to prove it.

1. Ask an adult to cut the top off a plastic drink bottle so it’s wide enough to put your hand in.

2. Place a layer of soil in the bottom of the bottle (about 3 cm).

 
3. Add a layer of plastic (about 5-10 cm). Use different types of plastics made of different colours. For example, plastic shopping bag, bread bag, piece of plastic cup.

4. Add more soil as well as old leaves, sawdust, grass, newspaper or food scraps (about 5-10 cm).

 
5. Sprinkle on some water. Tape the top back on the bottle and mark the levels of the layers in the bottle with a marker pen.

6. Put your bottle compost in a warm place (a window sill is perfect).

WHAT HAPPENED?
Watch your compost in a bottle for three or four weeks. The materials which break down shrink and change their shape and colour as they begin to rot. But the plastic doesn’t rot at all! What do you think this means for all the plastic lying around on the ground?