Traditionally black, normally dead.
Hint spray painting a rose black is not conducive to it's
survival.
Why carry a dead black rose??
'Cos it's dead of course.
If you're very lucky you might be able to give it to someone as part
of you gothic pickup
line however that isn't the point of it, and neither is it meant
as advertising, although if either approach looks like getting you a
free drink go for it.