How to change axis-label color in ggplot2?

Question

I have tried

... + xlab("New label", colour="darkgrey")

and

... + xlab("New label", color="darkgrey")

But it says this argument is unused. I look into ?xlab, but it doesn't include any color parameter. Is it possible to change it? How?

Answer 1

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.