Q: I want to wash black mold from a concrete wall next to plants ... Assuming that's really the cause, one product to try is Super Iron Out Rust Stain Remover (888-476-6688; www.superironout.com ...

One product that’s labeled for use on concrete, as well as numerous other materials, is Wet & Forget Moss, Mold, Mildew & Algae Stain Remover ($24.38 for a half gallon at Home Depot).

There are a variety of cleaning products available ... look for a bleach-free mold and mildew remover. Diluted liquid chlorine bleach removes mold from concrete, brick, stucco and other outdoor ...

Consumer expert Amy Davis is testing products to find ... We used a different remover on 6 different concrete pavers that were covered with blackish-green mold stains. Some, like Home Armor ...