Answer: As the pachysandra fills in it should be able to outcompete the weeds. You might spread a layer of dampened newspaper on the soil between the plants and cover that with an organic mulch layer several inches thick. This should prevent new weeds from sprouting and should smother existing weeds. If some pop their way through that, apply an herbicide containing glyphosate to control them, being careful to protect the pachysandra from any spray drift. A wipe-on application method may be easier to control. Follow the label instructions carefully and allow ample time for the chemical to translocate to the roots. Finally, make sure you don't let any of the weeds go to seed -- that's one of the biggest steps in getting a weed population under control.
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