ggplot with conditions

[mara]

The way you currently have things, fill_col is just another variable, as opposed to an _ aesthetic value_ that's evaluated by ggplot as a fill colour. See, for example the StackOverflow thread, below:

Histogram conditional fill color

There's an example included in the community thread, below, that shows you how to use a colour palette with specific colours matched to specific values using a named vector:

Setting colours in ggplot conditional on value

Try making your palette a named vector, with names matching your factor levels, in order to control which color gets matched to what. Per the docs: If this is a named vector, then the values will be matched based on the names. If unnamed, values will be matched in order (usually alphabetical) with the limits of the scale. The named vector approach is the recommended one (but this advice is a bit buried — it's mentioned in a comment to one of the examples in the docs). So in your case: #Colour Palette pal <- c( "Serious" = "red", "Significant" = "orange", "Minimal" = "yellow", "Strengths" = "forestgreen" ) df %>% ggplot(aes(x = factor, y = mean, fill = concern)) + geom_…