title: How to convert column to datetime ignoring obscure string values
body: <p>I am trying to convert several columns to datetime, most of which have worked, although one or two contain several unique string values that will not convert. The code I used is:</p>
  
  <pre><code>energy['EFD'] =  pd.to_datetime(energy['EFD'])
  </code></pre>
  
  <p>Most values for <code>'EFD'</code> are in the format <code>2011-05-31 00:00:00</code> however unlike my other columns it contains string values such as <code>'15 Months'</code>, <code>'36 months from start'</code> which messes up <code>.to_datetime</code>.</p>
  
  <p>Is there a way to ignore these and change the rest to datetime?</p>
  
  <p>Thanks</p>