I am trying to change the colours of the lines in a plot including two curves and 2 vertical lines, but it has been unsuccessful. Would you mind telling me how I can change my script below to assign a specifi colour to each of the 4 lines? Thanks a lot for your help!

```
data <- data.frame(day_of_year=rep(1:5, 4), variable=c('variable1', 'variable1', 'variable1', 'variable1', 'variable1', 'variable2', 'variable2', 'variable2', 'variable2', 'variable2', 'variable3', 'variable3', 'variable3', 'variable3', 'variable3', 'variable4', 'variable4', 'variable4', 'variable4', 'variable4'), value=c(12, 21, 35, 42, 56, 1, 4, 3, 4, 5, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4))

p1 <- ggplot(data=data)
p1 <- p1 + geom_line(data=data[data$variable=='variable1',], aes(x=day_of_year, y=value, colour='variable1'), size=0.5)
p1 <- p1 + geom_line(data=data[data$variable=='variable2',], aes(x=day_of_year, y=value*10, colour='variable2'), size=0.5)
p1 <- p1 + geom_vline(data=data[data$variable=='variable3',], aes(xintercept=value, colour='variable3'), linetype='dashed', size=0.5)
p1 <- p1 + geom_vline(data=data[data$variable=='variable4',], aes(xintercept=value, colour='variable4'), linetype='dashed', size=0.5)
p1 <- p1 + scale_colour_discrete(breaks=c("variable1","variable2","variable3", 'variable4'))
p1 <- p1 + labs(list(colour = "", title = "(A)", x = "Day of year", y =""))
p1 <- p1 + theme_bw()
p1 <- p1 + theme(title=element_text(size=7, face='bold', vjust=0.8, hjust = 0.5), axis.text.x=element_text(size=7), axis.text.y =element_text(size=8),legend.text=element_text(size=8),legend.title=element_text(size=8), axis.title=element_text(size=8, face='bold'))
p1 <- p1 + geom_text(x=1.5, y=50, label='fallow', size=3)
p1 <- p1 + geom_text(x=3, y=50, label='crop', size=3)
p1 <- p1 + geom_text(x=4.5, y=50, label='fallow',size=3)
p1

```

This is the graph I have for the moment with the default colours:
[![graph](https://i.stack.imgur.com/vvWef.png)](https://i.stack.imgur.com/vvWef.png)

I have tried to add the scripts below, but without success:

```
# p1 <- p1 + scale_colour_manual(values=c('red','black','dark grey','blue'))
# p1 <- p1 + scale_colour_discrete(value=c("blue", "red", "grey", 'black'))
# p1 <- p1 + scale_color_manual(value=c("#CC6666", "#9999CC", "#CC6666", "#9999CC"), breaks=c("variable1","variable2","variable3", 'variable4'))

```