planting where path used to be
I have lifted a number of slabs in the garden to create more space for plants but beneath the old slabs the earth is covered in concrete / cement powder (looks like grey sand). I don't think I want to grow any veg in this but I am unsure of how to get rid of it and how best to prepare the ground for planting. Will it even be safe to eat veg grown in this earth if I don't get it all?
I was thinking about removing as much as possible and digging manure in then putting down a cardboard mulch with compost on top.
all advice very welcome!