diff --git a/docker-compose.yml b/docker-compose.yml
index 7bc27dbe..e18a6b40 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -163,6 +163,9 @@ services:
       SPRING_DATASOURCE_URL: jdbc:postgresql://db:5432/${POSTGRES_DB}
       SPRING_DATASOURCE_USERNAME: ${POSTGRES_USER}
       SPRING_DATASOURCE_PASSWORD: ${POSTGRES_PASSWORD}
+      # Consumed by Flyway V68 via the ${grafanaDbPassword} placeholder to set
+      # the read-only grafana_reader role's password.
+      GRAFANA_DB_PASSWORD: ${GRAFANA_DB_PASSWORD}
       S3_ENDPOINT: http://minio:9000
       S3_ACCESS_KEY: ${MINIO_ROOT_USER}
       S3_SECRET_KEY: ${MINIO_ROOT_PASSWORD}