diff --git a/ca/renew.go b/ca/renew.go
index 44234781..5f888bf1 100644
--- a/ca/renew.go
+++ b/ca/renew.go
@@ -72,6 +72,8 @@ func NewTLSRenewer(cert *tls.Certificate, fn RenewFunc, opts ...tlsRenewerOption
 	if r.renewJitter == 0 {
 		r.renewJitter = period / 20
 	}
+	// Initialize certNotAfter
+	r.certNotAfter = cert.Leaf.NotAfter.Add(-1 * time.Minute)
 
 	return r, nil
 }