forget the dirt!
that's just an old wive's tale... a myth caused because of a lack of research. you see, it's the DOG CRAP that causes you to grow, NOT the dirt. the "dirt myth" was started due to ignorant people who ate dirt and experienced growth... not even realizing that they were often getting dog crap in their dirt. So they credited their growth to the dirt, not even thinking about the dog crap... and so the myth begn. my advice would be, FORGET THE DIRT, just EAT THE CRAP!