I Have this in my routes :
+--------+---------------------------+--------------+---------------------------
You CAN add css clases, and any type of attributes you need to blade template, try this:
{{ Form::open(array('url' => '/', 'method' => 'PUT', 'class'=>'col-md-12')) }}
.... wathever code here
{{ Form::close() }}
If you dont want to go the blade way you can add a hidden input. This is the form Laravel does, any way:
Note: Since HTML forms only support POST and GET, PUT and DELETE methods will be spoofed by automatically adding a _method hidden field to your form. (Laravel docs)