I can't seem to find much information on the internet for these scenes. At least nothing in English.
I did find one article on theforce.net that mentions a fan visit to Lake Como:
It refers to 3 filming locations in the area which includes a picnic meadow so this might be the right spot. The link in the article goes to a site in Italian and I can't find any reference to this trip. The only thing I found was an article about the locations in all 6 films but I've seen this on several sites before:
I think I'll try contacting them to see if they have any more information.