Print #field_suffix with drupal_render($form['field_custom_text_field']) I have a custom module that defines a field_suffix for a custom text field

function custom_check_form_user_register_form_alter(&amp;$form){ 
$form['field_url']['und'][0]['#field_suffix']='text goes here';
}


I then am calling the field in a user-register.tpl.php as

print drupal_render($form['field_reg_site_url']);


However, the #field_suffix isn't printing (checked that the value is in the array - yes). It does work (same code pattern) for username. Any ideas what I'm missing?
Try

$form['field_url']['#field_suffix']='text goes here';


Also, in your example, the suffix is being set on field_url but you are printing field_reg_site_url. That could be causing some confusion.