Bindweed in topsoil

Question ...

I have acquired some topsoil which unfortunately has some bindweed in it and I'm wondering about the best way to deal with it before planting in a raised bed. I was wondering about a stale seed bed or sowing Mexican marigold (Tagetes minuta, I think was recommended as inhibiting bindweed) or covering the soil with plastic or burning with a weed wand.

Which of these would be most effective and in which order should I try them?

Answer ...

If there are bindweed roots in the soil, I suggest that you go through the whole lot and remove them by hand. If the heap is too large to do that, then you could try putting it all through a riddle or seive. Spending the time to do this now will save endless frustration later. Once you have done that, then a stale seedbed, to catch bits that you missed, would be sensible. Mexican marigold would have no effect, and I don't think flame weeding would be effective. A black plastic mulch would have to stay in place for years to be effective. Alternatively, send the topsoil back. Knowingly introducing bindweed into a garden is not a good move.

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