Green’s Dictionary of Slang

rose n.²

an orange.

1860		Hotten Dict. of Modern Sl. etc. (2nd edn).
1864, 1867, 1870		Hotten Sl. Dict.

SE in slang uses

In phrases

gather a rose (v.)

a euph. meaning to urinate.

1678

J. Ray Proverbs (2nd edn) 88: To make water &c. [...] To make a little maids water. To water the Marigolds. To speak with a maid. To gather a rose.