diff --git a/templates/deployment-sidekiq.yaml b/templates/deployment-sidekiq.yaml
index d549819..ce012ff 100644
--- a/templates/deployment-sidekiq.yaml
+++ b/templates/deployment-sidekiq.yaml
@@ -212,7 +212,7 @@ spec:
             - name: PROMETHEUS_EXPORTER_HOST
               value: {{ $context.Values.mastodon.metrics.prometheus.host }}
             - name: PROMETHEUS_EXPORTER_PORT
-              value: {{ $context.Values.mastodon.metrics.prometheus.port }}
+              value: "{{ $context.Values.mastodon.metrics.prometheus.port }}"
             {{- if $context.Values.mastodon.metrics.prometheus.sidekiq.detailed }}
             - name: MASTODON_PROMETHEUS_EXPORTER_SIDEKIQ_DETAILED_METRICS
               value: "true"
@@ -223,7 +223,7 @@ spec:
             - name: MASTODON_PROMETHEUS_EXPORTER_HOST
               value: {{ $context.Values.mastodon.metrics.prometheus.sidekiq.local.host }}
             - name: MASTODON_PROMETHEUS_EXPORTER_PORT
-              value: {{ $context.Values.mastodon.metrics.prometheus.sidekiq.local.port }}
+              value: "{{ $context.Values.mastodon.metrics.prometheus.sidekiq.local.port }}"
             {{- end }}
             {{- end }}
           volumeMounts:
diff --git a/templates/deployment-web.yaml b/templates/deployment-web.yaml
index 3df2733..fb48b29 100644
--- a/templates/deployment-web.yaml
+++ b/templates/deployment-web.yaml
@@ -202,7 +202,7 @@ spec:
             - name: PROMETHEUS_EXPORTER_HOST
               value: {{ $.Values.mastodon.metrics.prometheus.host }}
             - name: PROMETHEUS_EXPORTER_PORT
-              value: {{ .Values.mastodon.metrics.prometheus.port }}
+              value: "{{ .Values.mastodon.metrics.prometheus.port }}"
             {{- if .Values.mastodon.metrics.prometheus.web.detailed }}
             - name: MASTODON_PROMETHEUS_EXPORTER_WEB_DETAILED_METRICS
               value: "true"