title: Matplotlib Subplot Labels Disappear
body: <p>I want to prepare some hexbin plots from Pandas. My initial code is:</p>
  
  <pre><code>fig = plt.figure(figsize=(11,8))
  ax1 = fig.add_subplot(111)
  
  df2.plot(kind='hexbin', x='var1', y='var2', C='var3', reduce_C_function=np.median,  gridsize=25,vmin=0, vmax=40,ax=ax1)
  ax1.set_xlim([-5,2])
  ax1.set_ylim([0,7])
  </code></pre>
  
  <p>However when I change this to:</p>
  
  <pre><code>fig = plt.figure(figsize=(11,8))
  ax1 = fig.add_subplot(221)
  ax2 = fig.add_subplot(222)
  ax3 = fig.add_subplot(223)
  ax4 = fig.add_subplot(224)
  </code></pre>
  
  <p>And plot create four subplots similar to the first example it turns off the xlabels and xticklabels.</p>
  
  <p>What code to I need to switch them back on? And is this something I can do as a defaults?</p>