diff --git a/include/mapnik/json/geometry_generator_grammar_impl.hpp b/include/mapnik/json/geometry_generator_grammar_impl.hpp
index e115c0188..202ad6d34 100644
--- a/include/mapnik/json/geometry_generator_grammar_impl.hpp
+++ b/include/mapnik/json/geometry_generator_grammar_impl.hpp
@@ -99,9 +99,9 @@ geometry_generator_grammar<OutputIterator, Geometry>::geometry_generator_grammar
         ;
     multi_point_coord = linestring_coord.alias()
         ;
-    multi_linestring_coord = linestring_coord % lit(',')
+    multi_linestring_coord = (lit('[') << linestring_coord << lit(']')) % lit(',')
         ;
-    multi_polygon_coord = polygon_coord % lit(',')
+    multi_polygon_coord = (lit('[') << polygon_coord << lit(']')) % lit(',')
         ;
     geometries =  geometry % lit(',')
         ;