A-blowin and a'goin

Does anyone know the origin of "a-blowin and a'goin?" I know what it means but not the origin.

London flower pot street vendors aka "Costers", sang out the phrase "All a-blowin' an' a-growin"


Chambers's Edinburgh Journalý - Page 68
by William Chambers, Robert Chambers - London (England) - 1852

Still, there are never wanting men of a speculative turn of mind, and the cry of
' All a-blowin' an' a-growin' ' resounds through the streets as long as the ...

The Cambridge Freshman; Or, Memoirs of Mr. Golightly ...ý
by James Rice, Hablot Knight Browne - English wit and humor - 1871 - 395 pages

"All a-blowin', a-growin' - a-blowin', a-growin' - a.growin', a-blowin' ! There,
gentlemen, buy a few pots o' nice flowers." ' "How much for the lot? ...

Just to clarify that "blowing" in this context means "blooming", as in "full-blown", "overblown" and Shakespeare's "I know a bank where the wild thyme blows". (VSD)