title: Adding three months to a date in PHP
body: <p>I have a variable called <code>$effectiveDate</code> containing the date <strong>2012-03-26</strong>.</p>
  
  <p>I am trying to add three months to this date and have been unsuccessful at it.</p>
  
  <p>Here is what I have tried:</p>
  
  <pre><code>$effectiveDate = strtotime("+3 months", strtotime($effectiveDate));
  </code></pre>
  
  <p>and </p>
  
  <pre><code>$effectiveDate = strtotime(date("Y-m-d", strtotime($effectiveDate)) . "+3 months");
  </code></pre>
  
  <p>What am I doing wrong? Neither piece of code worked.</p>