title: Merging two plots in ggplot2 and keeping individual features of the plots (geom_text, geom_vline)
body: <p>I have two geom_line time series with some geom_text &amp; geom_points on each plot.</p>
  
  <p>One of the two plots additionally has geom_vline. I wonder if it is possible to merge two but i failed to get a solution.</p>
  
  <p>Here are the two plots:</p>
  
  <pre><code>require(zoo)
  require(ggplot2)
  
  set.seed(10)
  
  # plot 1:
  tmp1 &lt;- xts(cumsum(rnorm(5000,1,10)), Sys.Date()-5000:1)
  data.tmp1 = data.frame(date=as.Date(index(tmp1)),
                        value=drop(coredata(tmp1)))
  data.tmp1.year.end = data.frame(date=as.Date(index(tmp1[endpoints(tmp1, "years", 1)])),
                                 value= drop(coredata(tmp1[endpoints(tmp1, "years", 1)])))
  
  plot1 = 
    ggplot(data.tmp1, aes(x=date, y=value)) +
    geom_line(aes(y=value), size=1) +
    geom_point(data=data.tmp1.year.end, col="red") +
    geom_text(data=data.tmp1.year.end, label=data.tmp1.year.end$value, vjust=0, hjust=1) 
  
  # plot 2:
  tmp2 &lt;- xts(cumsum(rnorm(5000,1,100)), Sys.Date()-5000:1)
  data.tmp2 = data.frame(date=as.Date(index(tmp2)),
                         value=drop(coredata(tmp2)))
  data.tmp2.year.end = data.frame(date=as.Date(index(tmp2[endpoints(tmp2, "years", 1)])),
                                  value= drop(coredata(tmp2[endpoints(tmp2, "years", 1)])))
  tmp2.date =as.Date(c("2008-01-01"))
  
  plot2 = 
    ggplot(data.tmp2, aes(x=date, y=value)) +
    geom_line(aes(y=value), size=1) +
    geom_point(data=data.tmp2.year.end, col="red") +
    geom_vline(xintercept=as.numeric(tmp2.date), linetype="dotted") +
    geom_text(data=data.tmp2.year.end, label=data.tmp2.year.end$value, vjust=0, hjust=1)
  </code></pre>
  
  <p>The goal now is that plot1 and plot2 share one xaxis and all features of the individual graphs are kept in the corresponding plot. </p>
  
  <p>The result should look like this:</p>
  
  <p><img src="https://i.stack.imgur.com/eDpdE.png" alt="enter image description here"></p>