Eliminating weeds in soil

I skimmed 3" of topsoil to get rid of any rubbish in it. Soon I will put it back down, spead it around. and then probably lay down grass turf on top of it.

But, last year a weed was growing on the pile of soil, grew everyhwhere. So, do I need to "sanitise" the soil heap I have, at least so I won't get weeds coming up thru the grass? Thanks.

 

It depends which weed it was on the soil, do you know what it was? The majority of annual weeds won't survive in a lawn anyway (or germinate and grow through turf) but it's the perennials you really have to watch. E.g if it was Rosebay willowherb you shouldn't have to worry, if it was bindweed it may be a different story.

When you say you skimmed the topsoil did you also remove any pernicious looking roots?

The organic way to deal with the soil would be spread and level your soil and let it settle for a good few weeks. Remove any perennial weeds by hand, root and all. Hoe off any annual weeds that establish. Wait a couple more weeks repeating the weeding as necesary then lay your turf.

The inorganic method is the same but rather than hand weeding and hoeing just nuke everything with glyphosate. < not the preferred method