I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
Without knowing the ingredient it is difficult to say how long the effect may last. If the product killed existing weeds it may be that you can already put down seeds. If it prevented weed seed from establishing it may take a couple of months before seed can be planted. If you can find out and submit another question to the website I'd be happy to try and help further.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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