Bought house and the garden is huge and completely dominated by stinging nettles. What can I do to kill them and not kill any of the other flowers?
You will have to pull up these plants to really control them in your garden.
I have this same issue in many areas of my garden, so I do understand the frustration.
The good news is that if you pull them when they first appear, you can get them under control pretty quickly.
Here are some articles with more information for you.
Just for fun I included some information on harvesting and eating Nettles!