Hello Christine W,
There are or were two places around Harpenden refered to as "Bluebell woods" during my time, late 1950s. A wood athe the top of Bowers Heath Lane at approximately a mile and half from Harpenden and of course the boy's wood within the grounds both were known by the name and could equally qualify. The boy's woods would have been visited within your normal play and it was quite common for families or groups such as brownies and cubs to visit the Bowers Heath woods. So you didn't make the name up but you now have the problem of knowing which you were referring to!
Sorry about that!