diff --git a/initdb.py b/initdb.py
index 311c3004e..50c2f4784 100644
--- a/initdb.py
+++ b/initdb.py
@@ -109,7 +109,7 @@ def __create_subtree(repo, structure, creator_username, parent, tag_map):
 
     new_image = model.image.set_image_metadata(docker_image_id, repo.namespace_user.username,
                                                repo.name, str(creation_time), 'no comment', command,
-                                               v1_metadata, parent)
+                                               json.dumps(v1_metadata), parent)
 
     compressed_size = random.randrange(1, 1024 * 1024 * 1024)
     model.image.set_image_size(docker_image_id, repo.namespace_user.username, repo.name,