No, no - Béal na mBláth (a neologism) would mean "Mouth of the Flowers" - the place was always Bealnablath in English, and in Irish was Béal na bPláth, "the moth of the inlet", pláth, apparently, being one of those old specialised geographical words meaning a river inlet. Though I don't know why that should be so; looking at Google Maps, Bealnablath doesn't seem to have ary a river near it at all. Perhaps water, as well as history, has been culverted there.