Hi there thanks for the Q.... the Hosta was Sielboldiana and is slug free purely because we use nematodes EARLY in the season. We created the garden in 2009 albeit we are still developing areas, but I make sure that I order and apply nematodes BEFORE damage is seen in early April. I get two more lots at 6 week intervals and after that you are laughing and have a lovely large population of nematodes working away. If you apply after damage has been seen, the nematodes might stop further damage but clever as they are they will not repair the original damage. Interestingly we tried copper tape around the raised beds elsewhere in the garden but I have pics of the slugs dancing on it. For a video of the garden look at www.gardendesignco.co.uk under 'Chiltern Estate'. Good luck and best wishes Rob