diff --git a/draggableviews.api.php b/draggableviews.api.php
index 0cb22c6..7a1a958 100644
--- a/draggableviews.api.php
+++ b/draggableviews.api.php
@@ -41,6 +41,6 @@ function hook_draggableviews_handler_native_arguments_alter(&$arguments, $view,
       }
     }
 
-    $form_values += $new_items;
+    $form_values = array_merge($form_values, $new_items);
   }
 }