I have a couple of areas where ground elder is taking over. i am waiting for a couple of sunny days to attack it with glyphosate. Meanwhile i am letting it get nice and leafy so that there is plenty of plant to spray as hopefully the larger surface area of leaf will carry more glyphosate to the root and kill it quicker.
When we bought this house, the garden had been neglected and consisted of nothing but ground elder. We lived with black plastic for a year and managed to choke it off, but it does come back under the fence from next door. Careful digging or glyphosate are your best bet.
It is all through our border, near our hedge. I think it was under control before I became pregnant in 2009, but since January 2010 (when my son was born) I haven't had much time to garden. Each spring, I plant some daffodils and tulips, and the gardens are looking colourful now, but the ground elder is a big problem. Today I tackled a 4' x 3' area, and it was back breaking work. I dug down with a spade about a foot, took out all the ground elder & roots that I could find, and carefully avoided the tulips. Is this the best way to do this? Should I just wait until autumn? It is taking all the nutrients and space from my plants!