ggplot: Edit x axis breaks

Question

I want to create a scatter plot showing daily heart rate, but with the x-axis showing month not day.

I would like the plot to look something like this:

With the code below I have created the following plot:

Sheep_1784 %>%
  ggplot(aes(x=Date, y=HeartRate)) + 
  geom_point()+
  theme_bw() +
  xlab("Month") + 
  ylab("HeartRate") 

Can you please advise how I can change the axis of my plot (second plot) to look like the first plot.