Spray bleach on moldy sidewalks and it be gone!
Clorox should have "stage of life" detergents, people with small children, families with teens for with lots of muddy sports, etc.
I use equal parts water and clorox bleach to wash my wood deck.
I let it dry and then apply a sealer. The bleach gets rid of all that old dirt and mold.
Works very good when dissinfecting tools and areas of the butcher shop when used daily.
Sell diluted mix of bleach for basement mold in a spray bottle.