plot solo meses de diferentes años

library(zoo)
library(lubridate)
library(ggplot2)

set.seed(49)
dat1 = data.frame(date = seq(as.Date("2015-01-15"), as.Date("2015-12-15"), "1 month"),
                  value = cumsum(rnorm(12)))
dat1$date = as.yearmon(dat1$date)

dat2 = data.frame(date = seq(as.Date("2016-01-15"), as.Date("2016-12-15"), "1 month"),
                  value = cumsum(rnorm(12)))
dat2$date = as.yearmon(dat2$date)

ggplot(rbind(dat1,dat2), 
       aes(month(date, label=TRUE, abbr=TRUE),
           value, group=factor(year(date)), colour=factor(year(date)))) +
  geom_line() +
  geom_point() +
  labs(x="Month", colour="Year") +
  theme_classic()


df <- tibble::tribble(
  ~fecha_de_siembra_dia_mes,      ~variedad, ~rinde, ~campana,
  "2021-06-15", "BAGUETTE_802", 6338.6,  "17-18",
  "2017-06-10", "BAGUETTE_802", 7518.3,  "17-18",
  "2017-06-13", "BAGUETTE_802",   6027,  "17-18",
  "2018-05-25", "BAGUETTE_802",   4400,  "18-19",
  "2018-06-10", "BAGUETTE_802",   5800,  "18-19",
  "2018-06-20", "BAGUETTE_802",   6250,  "18-19",
  "2019-06-04", "BAGUETTE_802",   4300,  "19-20",
  "2019-07-16", "BAGUETTE_501",   6500,  "19-20",
  "2019-06-10", "BAGUETTE_802",   6150,  "19-20",
  "2020-08-02", "BAGUETTE_501",   6100,  "20-21",
  "2020-07-20", "BAGUETTE_501",   6020,  "20-21",
  "2020-06-09", "BAGUETTE_802",   6751,  "20-21"
)

df %>% mutate(
  year = factor(year(as.Date(fecha_de_siembra_dia_mes))),     
  date = update(as.Date(fecha_de_siembra_dia_mes), year = 1)) %>% 
  ggplot(aes(date, rinde, col =year)) +
  facet_grid(variedad~., scales="free_x")+
  geom_point()