I first learned "Green grow the rushes-oh" at primary school and very much enjoyed singing it. The version that I sing nowadays can be found in Folk Songs of the British Isles
. I can remember it being sung with light modifications in the Royal Navy in the 1950's and 1960's. All I can now recall is the substitution of the sea boot's crew
instead of the lily white boys
in the second verse.
It is a fine jolly accumulative song and quite a tongue-twister.