Question: Make your own potting soil.
Options:
Go outside and dig up some dirt. Carefully spread thin on a cookie sheet and bake for 10 minutes. This kills all germs.
Go outside and dig up some dirt. Carefully spread thin on a cookie sheet and let sit in sun for 10 minutes. This kills all germs.
Answer: Go outside and dig up some dirt. Carefully spread thin on a cookie sheet and bake for 10 minutes. This kills all germs.