diff --git a/pkg/util/cmapichecker/BUILD.bazel b/pkg/util/cmapichecker/BUILD.bazel
index 0b4ce65d6..34405fa15 100644
--- a/pkg/util/cmapichecker/BUILD.bazel
+++ b/pkg/util/cmapichecker/BUILD.bazel
@@ -6,7 +6,7 @@ go_library(
     importpath = "github.com/jetstack/cert-manager/pkg/util/cmapichecker",
     visibility = ["//visibility:public"],
     deps = [
-        "//pkg/apis/certmanager/v1alpha2:go_default_library",
+        "//pkg/apis/certmanager/v1:go_default_library",
         "//pkg/apis/meta/v1:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
         "@io_k8s_apimachinery//pkg/apis/meta/v1:go_default_library",
@@ -35,7 +35,7 @@ go_test(
     srcs = ["cmapichecker_test.go"],
     embed = [":go_default_library"],
     deps = [
-        "//pkg/apis/certmanager/v1alpha2:go_default_library",
+        "//pkg/apis/certmanager/v1:go_default_library",
         "@io_k8s_apimachinery//pkg/runtime:go_default_library",
         "@io_k8s_sigs_controller_runtime//pkg/client:go_default_library",
         "@io_k8s_sigs_controller_runtime//pkg/client/fake:go_default_library",
diff --git a/pkg/util/cmapichecker/cmapichecker.go b/pkg/util/cmapichecker/cmapichecker.go
index e9dbd6477..dbb396421 100644
--- a/pkg/util/cmapichecker/cmapichecker.go
+++ b/pkg/util/cmapichecker/cmapichecker.go
@@ -27,11 +27,7 @@ import (
 	"k8s.io/client-go/rest"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
-	// Use v1alpha2 API to ensure that the API server has also connected to the
-	// cert-manager conversion webhook.
-	// TODO(wallrj): Only change this when the old deprecated APIs are removed,
-	// at which point the conversion webhook may be removed anyway.
-	cmapi "github.com/jetstack/cert-manager/pkg/apis/certmanager/v1alpha2"
+	cmapi "github.com/jetstack/cert-manager/pkg/apis/certmanager/v1"
 	cmmeta "github.com/jetstack/cert-manager/pkg/apis/meta/v1"
 )
 
@@ -81,11 +77,13 @@ func New(restcfg *rest.Config, scheme *runtime.Scheme, namespace string) (Interf
 	}, nil
 }
 
-// Check attempts to perform a dry-run create of a cert-manager *v1alpha2*
+// Check attempts to perform a dry-run create of a cert-manager
 // Certificate resource in order to verify that CRDs are installed and all the
 // required webhooks are reachable by the K8S API server.
-// We use v1alpha2 API to ensure that the API server has also connected to the
-// cert-manager conversion webhook.
+// Originally we used the v1alpha2 API to ensure that the API server has also
+// connected to the cert-manager conversion webhook, but since cert-manager 1.6
+// we have disabled the serving of non-v1 CRD versions, so it is no longer
+// possible to test the reachability of the conversion webhook.
 func (o *cmapiChecker) Check(ctx context.Context) error {
 	cert := &cmapi.Certificate{
 		ObjectMeta: metav1.ObjectMeta{
@@ -135,13 +133,10 @@ func (e *ApiCheckError) Unwrap() error {
 // - error finding the scope of the object: failed to get restmapping: no matches for kind "Certificate" in group "cert-manager.io"
 // ErrWebhookServiceFailure:
 // - Internal error occurred: failed calling webhook "webhook.cert-manager.io": Post "https://cert-manager-webhook.cert-manager.svc:443/mutate?timeout=10s": service "cert-manager-webhook" not found
-// - conversion webhook for cert-manager.io/v1alpha2, Kind=Certificate failed: Post "https://cert-manager-webhook.cert-manager.svc:443/convert?timeout=30s": service "cert-manager-webhook" not found
 // ErrWebhookDeploymentFailure:
 // - Internal error occurred: failed calling webhook "webhook.cert-manager.io": Post "https://cert-manager-webhook.cert-manager.svc:443/mutate?timeout=10s": dial tcp 10.96.38.90:443: connect: connection refused
-// - conversion webhook for cert-manager.io/v1alpha2, Kind=Certificate failed: Post "https://cert-manager-webhook.cert-manager.svc:443/convert?timeout=30s": dial tcp 10.96.38.90:443: connect: connection refused
 // ErrWebhookCertificateFailure:
 // - Internal error occurred: failed calling webhook "webhook.cert-manager.io": Post "https://cert-manager-webhook.cert-manager.svc:443/mutate?timeout=10s": x509: certificate signed by unknown authority (possibly because of "x509: ECDSA verification failure" while trying to verify candidate authority certificate "cert-manager-webhook-ca")
-// - conversion webhook for cert-manager.io/v1alpha2, Kind=Certificate failed: Post "https://cert-manager-webhook.cert-manager.svc:443/convert?timeout=30s": x509: certificate signed by unknown authority
 func translateToSimpleError(err error) error {
 	s := err.Error()
 
diff --git a/pkg/util/cmapichecker/cmapichecker_test.go b/pkg/util/cmapichecker/cmapichecker_test.go
index cd8f5638e..0cc3c0d4b 100644
--- a/pkg/util/cmapichecker/cmapichecker_test.go
+++ b/pkg/util/cmapichecker/cmapichecker_test.go
@@ -26,7 +26,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/client/fake"
 
-	cmapi "github.com/jetstack/cert-manager/pkg/apis/certmanager/v1alpha2"
+	cmapi "github.com/jetstack/cert-manager/pkg/apis/certmanager/v1"
 )
 
 type fakeErrorClient struct {