Control jitter width to allow overlapping of categories ggplot2 - r

Question

I have a dataset looking like this:
Flowers Sun_Exposition Value Repl
1: Tulipe mid 87.9 Aa1
2: Tulipe mid 92.8 Aa2
3: Tulipe mid 86.4 Aa3
4: Tulipe mid 83.3 Aa4
5: Tulipe mid 91.3 Aa5-1
6: Tulipe mid 91.4 Aa5-2
Flowers having two categories and there is 4 different Sun exposition. For each combination I have a different number of replicates.
I would like to plot a barplot (with sd) with also the points shaped by replicates.
Here is my code:
# summarize data
dataSum <- data[, .(M = mean(Value, na.rm = T), S = sd(Value, na.rm = T)),
by = .(Flowers, Sun_Exposition)]
# the plot
p <- ggplot(dataSum, aes(x = Sun_Exposition, y = M, fill = Flowers)) +
geom_bar(stat = "identity", color = "black",
position = position_dodge(.9)) +
geom_errorbar(aes(ymin = M, ymax = M + S), width = .2,
position = position_dodge(.9)) +
geom_jitter(data = data,
mapping = aes(x = Sun_Exposition, y = Value,
fill = Flowers,
shape = Repl, color = Flowers),
size = 2,
position = position_dodge(width = 0.9)) +
scale_shape_manual(values = c(19,17,18,15,7,8,6,5,4,2,13,12,3))+
scale_fill_manual(values = c("gray", "lavender")) +
scale_color_manual(values = c("gray30", "mediumpurple"))
which gives me this plot:
My problem is that the "spread" of the points is not as width as the width of the bar. I have tried many combination, such as using geom_point, and position_jitterdodge, putting the jitter width to 0 or negative but it never gave the results I wanted.
Thank you very much for your help!

Answer 1

You have to add a group mapping to the aesthetics of geom_jitter. On your data, I suppose you would have to add group = Flowers.
Here is an example with mtcars:
library(magrittr)
library(dplyr)
library(ggplot2)
library(forcats)
mt1 <- mtcars %>%
group_by(cyl, am) %>%
summarize(mean = mean(hp, na.rm = T),
sd = sd(hp, na.rm = T))
mt2 <- mtcars %>%
mutate(rep = paste0("rep", rep(1:8, each = 4)))
# the plot
ggplot(mt1, aes(x = as_factor(cyl),
y = mean,
fill = as_factor(am))) +
geom_bar(stat = "identity", color = "black",
position = position_dodge(.9)) +
geom_errorbar(aes(ymin = mean, ymax = mean + sd), width = .2,
position = position_dodge(.9)) +
geom_jitter(data = mt2,
aes(x = as_factor(cyl),
y = hp,
fill = as_factor(am),
shape = as_factor(rep),
color = as_factor(am),
group = as_factor(am)),
size = 1,
position = position_jitterdodge(jitter.width = 0.9)) +
scale_shape_manual(values = c(19,17,18,15,7,8,6,5,4,2,13,12,3))+
scale_fill_manual(values = c("gray", "lavender")) +
scale_color_manual(values = c("red", "blue"))