diff --git a/bin/jekyll b/bin/jekyll
index db912011..0eea75e0 100755
--- a/bin/jekyll
+++ b/bin/jekyll
@@ -17,7 +17,7 @@ default_command :help
 global_option '-s', '--source [DIR]', 'Source directory (defaults to ./)'
 global_option '-d', '--destination [DIR]', 'Destination directory (defaults to ./_site)'
 global_option '--safe', 'Safe mode (defaults to false)'
-global_option '--plugins', 'Plugins directory (defaults to ./_plugins)'
+global_option '--plugins PLUGINS_DIR1[,PLUGINS_DIR2[,...]]', Array, 'Plugins directory (defaults to ./_plugins)'
 global_option '--layouts', 'Layouts directory (defaults to ./_layouts)'
 
 # Option names don't always directly match the configuration value we'd like.