Another item, this time from the Irish Examiner (formerly The Cork Examiner) which may put to rest the meaning of the place where Michael Collins was killed. It is definitely not a place where flowers grow at least not when I visited it several years ago.

"August 24,2001
Béalnabláth is correct name
NOW that Michael Collins' commemoration has come round once again, I do wish journalists would try to get the name of the ambush area right.
It is not Béal na mBláth but Béalnabláth and derives not from "bláth" meaning a flower, but from "Blagha" meaning a ravine.
The name itself means "the crossing of the ravine" which is situated at the present village and was used by carriages in the old days. It is about a kilometre from where Collins was killed.
The "mouth of the flowers" translation is a mistake which has been repeated and repeated ever since it was first wrongly used by an English journalist on Wednesday August 23,1922, the day after Collins had died.

Rev Patrick J Twohig, PP,
Parochial House,
Churchtown,
Mallow,
Co Cork."
And there speaks a man with some authority.