Ginger for Luck

The ditty you quoted did not appear in my search results. However, the "ginger for pluck" saying seems to have been commonplace by 1859, when the first print use I could uncover appears on 26 Oct in The Standard (London, Greater London, England; paywalled, emphasis mine):

One of the females, named Hannah Hore, called after him "Ginger for pluck," ....

Joseph Wright's English Dialect Dictionary, v. 2 (1900), in the entry defining 'ginger' as a "light red or yellow colour", quotes "ginger for pluck" and sources his quote of the saying to J. Ellett Brogden's 1866 Provincial Words and Expressions Current in Lincolnshire (London). I was unable to find the Brogden work online.

J.S. Farmer and W.E. Henley, in the 1893 Slang and its Analogues Past and Present note "Whence the phrase (venery) 'Black for beauty, GINGER for pluck'" in their entry for 'ginger' in the sense of a "red-haired person".

In the circa 1870 (likely 1873 or 1878) novel Arab Jack, 'ginger for pluck' is described as an "old adage":

...as Nina used to say when she was in her teasing moods that my bright golden locks were ginger, you will find the old adage 'ginger for pluck' is quite true, ....

The adage continues in use through the later decades of the 1800s and into the 1900s, when, by 1917, the happy consonance (I am, or rather was, a ginger myself) of luck and pluck is exploited in a song titled "Ginger", by Bernard Moore:

"Ginger for pluck," we told him, an' squeezed him in the boat;
"Ginger for luck," he answered, "'twas my hair keeped me afloat."