Agree. Purple Dead Nettle. If they are not bothering you, let them stay until you need the space because bees love these flowers and they provide nectar source earlier in the season when there are not as many choices.
In my garden they yellow and get tattered looking when it gets hot. By then other options are available for the bees so I get rid of them as I need the space for planting other things and start mulching in earnest.
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