R: How to Make Heat Map with Values and Custom Scale Colors

Question

I am attempting to make a Heat Map in R. I would like to have the values displayed inside the boxes. I also would like to custom scale it with Red being 0.170, White being 0.260, and Blue being 0.356. Here is my code so far along with my dataframe:

RHPLowVelHeatMap <- read.csv("HeatMap RHP Low Vel.csv")
rownames(RHPLowVelHeatMap)[1:5] <- c("Very High", "High", "Dead", 
"Low", "Very Low")

y <- data.matrix(RHPLowVelHeatMap)


heatmap.2(y, col = colorpal1, main = "Sample", trace = "none", Rowv = 
FALSE, Colv = FALSE)
colorpal1 <- colorRampPalette(c("red", "lightblue","blue"))

Thank you all in advance!