Coloring boxplot outlier points in ggplot2?

Question

How can I color the outlier points in ggplot2? I want them to be the same color as the boxplot itself. colour= is not enough to do this.

Example:

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Answer 1

If there is a need to change shape or color of the outlier points according to different factor (not the same which is used for making boxplot groups) then answer of @Dinre can be adapted.

Color of points can be changed only if the color isn't used for boxplot themselves (you can't use two variables for colors).

Using the data plot_Data and code from the @Dinre answer - color of outliers depend on factor carb. By adding argument outlier.shape = NA to geom_boxplot() original outliers are removed to ensure that they are not over-plotted by geom_point().

ggplot() +
  geom_boxplot(data=plot_Data, aes(x=factor(cyl), y=mpg),outlier.shape = NA) + 
  geom_point(data=plot_Data[plot_Data$mpg > plot_Data$upper.limit | 
                              plot_Data$mpg < plot_Data$lower.limit,], 
             aes(x=factor(cyl), y=mpg, color=factor(carb)))

To change the shape of points:

ggplot() +
  geom_boxplot(data=plot_Data, aes(x=factor(cyl), y=mpg),outlier.shape = NA) + 
  geom_point(data=plot_Data[plot_Data$mpg > plot_Data$upper.limit | 
                              plot_Data$mpg < plot_Data$lower.limit,], 
             aes(x=factor(cyl), y=mpg, shape=factor(carb)))