diff --git a/internal/catalog/item_repo.go b/internal/catalog/item_repo.go
index 2b917837..e6b31719 100644
--- a/internal/catalog/item_repo.go
+++ b/internal/catalog/item_repo.go
@@ -1240,6 +1240,15 @@ func (r *ItemRepository) UpdateMetadata(ctx context.Context, contentID string, u
 			argIdx++
 		}
 	}
+	// addNullableString behaves like addString but stores an empty string as SQL
+	// NULL (via NULLIF), so clearing a nullable column persists as NULL.
+	addNullableString := func(col string, val *string) {
+		if val != nil {
+			setClauses = append(setClauses, fmt.Sprintf("%s = NULLIF($%d, '')", col, argIdx))
+			args = append(args, *val)
+			argIdx++
+		}
+	}
 	addInt := func(col string, val *int) {
 		if val != nil {
 			setClauses = append(setClauses, fmt.Sprintf("%s = $%d", col, argIdx))
@@ -1289,7 +1298,7 @@ func (r *ItemRepository) UpdateMetadata(ctx context.Context, contentID string, u
 	addString("first_air_date", upd.FirstAirDate)
 	addString("last_air_date", upd.LastAirDate)
 	addString("air_time", upd.AirTime)
-	addString("air_timezone", upd.AirTimezone)
+	addNullableString("air_timezone", upd.AirTimezone)
 	addString("status", upd.Status)
 	addString("show_status", upd.ShowStatus)
 	addString("imdb_id", upd.ImdbID)
diff --git a/web/src/components/EditMetadataDialog.tsx b/web/src/components/EditMetadataDialog.tsx
index 9d54429d..053da6e0 100644
--- a/web/src/components/EditMetadataDialog.tsx
+++ b/web/src/components/EditMetadataDialog.tsx
@@ -185,7 +185,10 @@ export default function EditMetadataDialog({ item, open, onOpenChange }: EditMet
       data.last_air_date = form.last_air_date || null;
     if (form.air_time !== originalForm.air_time) data.air_time = form.air_time || null;
     if (form.air_timezone !== originalForm.air_timezone)
-      data.air_timezone = form.air_timezone || null;
+      // Send "" (not null) when cleared: the server treats null as "skip", so
+      // clearing a previously-set timezone would not persist. "" is accepted by
+      // validation and normalized to NULL server-side.
+      data.air_timezone = form.air_timezone;
     if (form.air_date !== originalForm.air_date) data.air_date = form.air_date || null;
     if (form.status !== originalForm.status) data.status = form.status;
     if (form.rating_imdb !== originalForm.rating_imdb) data.rating_imdb = form.rating_imdb;