I have tried
... + xlab(\"New label\", colour=\"darkgrey\")
and
... + xlab(\"New label\", color=\"darkgrey\")
Since ggplot2 0.9.2, the syntax has become:
dat <- data.frame(x = 1:5,y = 1:5)
p + theme(axis.title.x = element_text(colour = "red"),
axis.title.y = element_text(colour = "blue"))
The tidyverse page is a good starting point for learning about all the options.
Note that the old syntax based on opts
has been deprecated. There is detailed transition guide for updating your code.