In a form after submitting all fields get cleared other than the TEXTAREA. I use summernote for textarea. (using bootstrap)
<script type='text/javascript'>//<![CDATA[
$(function(){
$('#description').summernote({height: 500});
});//]]>
</script>
#description
is the id of the textarea.
reset done like below
<script>
$('#submit-box')[0].reset();
</script>
#submit-box
is the id of the form
$('#description').code('');
see http://hackerwins.github.io/summernote/features.html#api-code
Updated
Since summernote v0.6.4+(maybe), the API has breaking changes.
$('#description').summernote('code', '');