diff --git a/functions b/functions
index 75c028b..deffc1b 100755
--- a/functions
+++ b/functions
@@ -402,6 +402,6 @@ service_linked_apps() {
 
 update_plugin_scheme_for_app() {
   local APP=$1
-  local POSTGRES_DATABASE_SCHEME=$(config_get $APP POSTGRES_DATABASE_SCHEME)
+  local POSTGRES_DATABASE_SCHEME=$(config_get "$APP" POSTGRES_DATABASE_SCHEME)
   PLUGIN_SCHEME=${POSTGRES_DATABASE_SCHEME:-$PLUGIN_SCHEME}
 }