A bio dome is a container for growing plants that doesn't need watering.
Steps to be taken
1. Check with a grown-up before you begin. Cutting soda bottles can be pretty tricky.
2. Start by removing the labels from 3 two-litre soda bottles.
3. First, cut the first bottle 2 to 3 centimetres above the top curve and then cut off the bottom of the same bottle 2 to 3 centimetres below the bottom curve.
4. Cut the top off the second bottle 2 centimetres below the top curve.
5. Cut the bottom off the third bottle 2 to 3 centimetres above the bottom curve.
6. Poke a hole in one cap with a thumb tack and enlarge it with scissors so you can get the string through. Attach the cap to the remaining top. Soak the cotton string in water and run it through the hole in the cap. The wick draws water into the soil.
7. Invert the capped top into the remaining bottom.
8. Slide the cylinder into it, and add the short top as a cover.
9. Fill the bottom part with water until it touches the cap.
10. Add soil in the capped section but make sure that the string runs up into the soil and is not stuck along the sides.
11. Now you're ready to plant and watch things grow.
12. Poke a 2 centimetre deep hole in the dirt and drop in a seed.
13. Cover the seed with some dirt.
14. Add a little water until the soil is moist.
15. Put the cap on and your bio dome is all set. Everything your plant needs to live is in there! It's got nutrients in the soil, lots of air in the bottles and water that gets soaked up through the string. All you need to do is find a sunny spot to put this because plants need sunlight to make their own food!