Have sprayed them and despite a slow start they are now wilting and turning yellow. Question is, do I cut them down or pull them out by the stems? Will they grow back? Best way of getting rid please. They are on a small front lawn part of which is now also dying off but had to get rid of them somehow.
leave them absolutely alone. If you pull or cut them now, the roots will survive and regrow. Cut off the seedheads if you have any and leave the rest until they are completely dead and dry
It depends what you sprayed them with. If you used a systemic weedkiller which would usually be Glyphosate based (eg Roundup), you can pull them up as the roots will be dead.
hammerman, i know from bitter experience that this is not true. I have known nettles regrow from their roots a month and longer after they were treated and looked dead. To be sure, leave the whole thing until its completely dried out.