For the extra tough stains that won’t come off with just a simple soap or limestone detergent, you may need to use a limestone stain remover. Yet, before you use any stain remover make sure that it is made for limestone, as many are not alkaline-based. Whether you make your own alkaline-based poultice or buy one, they will work to take out the oils and stains without destroying the limestone.
Limestone is extremely porous when compared to other kinds of stone. As such, limestone stain removal can be a little tricky. You cannot exactly use the same tactics in limestone stain removal that you would if cleaning a concrete patio. Instead, use these step-by-step instructions and you should have a clean, stain-free limestone patio.