diff --git a/panels.module b/panels.module
index 6a5d1ffc81912a56fe384381f3442d2ca7db6fd0..83658c431ebc09dee634a5073ec3ba29ea506873 100644
--- a/panels.module
+++ b/panels.module
@@ -1176,7 +1176,7 @@ function panels_render_display(&$display, $renderer = NULL) {
     if ($form_context = ctools_context_get_form($display->context)) {
       $form_context->form['#theme'] = 'panels_render_display_form';
       if (empty($form_context->form['#theme_wrappers']) || !in_array('form', $form_context->form['#theme_wrappers'])) {
-        $form_context['#theme_wrappers'][] = 'form';
+        $form_context->form['#theme_wrappers'][] = 'form';
       }
       $form_context->form['#display'] = &$display;
       return $form_context->form;