diff --git a/lib/manager/kustomize/readme.md b/lib/manager/kustomize/readme.md
index 33fef75469d6ea608db5b7caa59f7d492863c217..28ceebdcb3099abe22a54f0786326d6ee4c35c01 100644
--- a/lib/manager/kustomize/readme.md
+++ b/lib/manager/kustomize/readme.md
@@ -12,8 +12,9 @@ This package will manage two parts of the `kustomization.yaml` file:
 
 **Limitations**
 
+- Needs to have `kind: Kustomization` defined
 - Currently this hasn't been tested using https to fetch the repos
-- the image tags are limited to the following formats:
+- The image tags are limited to the following formats:
 
 ```
 - name: image/name