diff --git a/.github/workflows/cd.yml b/.github/workflows/cd.yml
index 1ee8c3eef..3f3dc7540 100644
--- a/.github/workflows/cd.yml
+++ b/.github/workflows/cd.yml
@@ -42,14 +42,6 @@ env:
   # updating.
   #
   HELM_VERSION: "v3.12.0"
-  # cert-mangaer versions at https://cert-manager.io/docs/release-notes/, update
-  # to latest when updating and make sure to read upgrade notes. "kubectl apply"
-  # will be done on CRDs but sometimes more is needed.
-  #
-  # NOTE: Updates to CERT_MANAGER_VERSION should also be done in the
-  #       test-helm-template.yaml workflow.
-  #
-  CERT_MANAGER_VERSION: "v1.12.0"
 
   # These variables influence git directly
   # https://git-scm.com/book/en/v2/Git-Internals-Environment-Variables#_committing
diff --git a/.github/workflows/test-helm-template.yaml b/.github/workflows/test-helm-template.yaml
index 92dfe4c3d..b396c147e 100644
--- a/.github/workflows/test-helm-template.yaml
+++ b/.github/workflows/test-helm-template.yaml
@@ -3,12 +3,6 @@
 #
 name: Test helm template --validate
 
-env:
-  # NOTE: Updates to CERT_MANAGER_VERSION should also be done in the cd.yaml
-  #       workflow.
-  #
-  CERT_MANAGER_VERSION: "v1.8.0"
-
 on:
   pull_request:
     paths:
@@ -74,10 +68,13 @@ jobs:
       # from cert-manager.
       #
       - name: Install cert-manager CRDs
-        run: kubectl apply -f https://github.com/jetstack/cert-manager/releases/download/${CERT_MANAGER_VERSION}/cert-manager.crds.yaml
+        run: |
+          . cert-manager.env
+          kubectl apply -f https://github.com/jetstack/cert-manager/releases/download/${CERT_MANAGER_VERSION}/cert-manager.crds.yaml
 
       - name: "helm template --validate (cert-manager chart)"
         run: |
+          . cert-manager.env
           echo "cert-manager version: ${CERT_MANAGER_VERSION}"
 
           helm template --validate cert-manager cert-manager \
diff --git a/cert-manager.env b/cert-manager.env
new file mode 100644
index 000000000..965183bf6
--- /dev/null
+++ b/cert-manager.env
@@ -0,0 +1,5 @@
+# cert-manager versions at https://cert-manager.io/docs/release-notes/, update
+# to latest when updating and make sure to read upgrade notes. "kubectl apply"
+# will be done on CRDs but sometimes more is needed.
+
+export CERT_MANAGER_VERSION=v1.12.0
diff --git a/deploy.py b/deploy.py
index dfe9e454d..dbdca8db8 100755
--- a/deploy.py
+++ b/deploy.py
@@ -227,7 +227,9 @@ def setup_certmanager():
     additional upgrade notes, see https://cert-manager.io/docs/release-notes/
     before you upgrade to a new version.
     """
-    version = os.environ["CERT_MANAGER_VERSION"]
+    version = os.getenv("CERT_MANAGER_VERSION")
+    if not version:
+        raise RuntimeError("CERT_MANAGER_VERSION not set. Source cert-manager.env")
 
     manifest_url = f"https://github.com/jetstack/cert-manager/releases/download/{version}/cert-manager.crds.yaml"
     print(BOLD + GREEN + f"Installing cert-manager CRDs {version}" + NC, flush=True)