diff --git a/management/commands/refresh_activities.py b/management/commands/refresh_activities.py
index b83e5a0..dd525d3 100644
--- a/management/commands/refresh_activities.py
+++ b/management/commands/refresh_activities.py
@@ -168,7 +168,7 @@ class Command(BaseCommand):
     def add_arguments(self, parser):
         parser.add_argument("--human", "-H", action="store_true", help="Save human readable page")
         parser.add_argument("--raw", "-r", action="store_true", help="Save raw page, for the calendar")
-        parser.add_argument("--comment", "-c", action="store", type=str, help="Comment of the modification")
+        parser.add_argument("--comment", "-c", action="store", type=str, default="", help="Comment of the modification")
         parser.add_argument("--debug", "-d", action="store_true", help="Don't commit to the wiki, render in stdout")
 
     def handle(self, *args, **options):