diff --git a/defaults/main.yml b/defaults/main.yml
index 5de84ad..5e55acc 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -3,7 +3,7 @@ certbot_work_dir: /var/lib/letsencrypt
 certbot_config_dir: /etc/letsencrypt
 certbot_log_dir: /var/log/letsencrypt
 certbot_environment:
-  - {{ certbot_work_dir }}
-  - {{ certbot_config }}
-  - {{ certbot_log_dir }}
+  - "{{ certbot_work_dir }}"
+  - "{{ certbot_config_dir }}"
+  - "{{ certbot_log_dir }}"
 certbot_user: root