diff --git a/core/modules/aggregator/aggregator.install b/core/modules/aggregator/aggregator.install
index 84e96147488d11c4ade897d5244498c2c1749282..8722892093b5f35460c97f499c848acefe8d8c17 100644
--- a/core/modules/aggregator/aggregator.install
+++ b/core/modules/aggregator/aggregator.install
@@ -40,3 +40,13 @@ function aggregator_update_8200() {
   $field_definition->setRequired(TRUE);
   $definition_update_manager->updateFieldStorageDefinition($field_definition);
 }
+
+/**
+ * Add a default value for the 'Refresh' field for aggregator feed entities.
+ */
+function aggregator_update_8501() {
+  $definition_update_manager = \Drupal::entityDefinitionUpdateManager();
+  $field_definition = $definition_update_manager->getFieldStorageDefinition('refresh', 'aggregator_feed');
+  $field_definition->setDefaultValue(3600);
+  $definition_update_manager->updateFieldStorageDefinition($field_definition);
+}
diff --git a/core/modules/aggregator/src/Controller/AggregatorController.php b/core/modules/aggregator/src/Controller/AggregatorController.php
index 0090ca31076f62e8de546adf45ea8ca53f22b417..b459b196ccbd441011649218a73f73ec7dbd91e7 100644
--- a/core/modules/aggregator/src/Controller/AggregatorController.php
+++ b/core/modules/aggregator/src/Controller/AggregatorController.php
@@ -47,10 +47,7 @@ public static function create(ContainerInterface $container) {
    *   A form array as expected by drupal_render().
    */
   public function feedAdd() {
-    $feed = $this->entityManager()->getStorage('aggregator_feed')
-      ->create([
-        'refresh' => 3600,
-      ]);
+    $feed = $this->entityManager()->getStorage('aggregator_feed')->create();
     return $this->entityFormBuilder()->getForm($feed);
   }
 
diff --git a/core/modules/aggregator/src/Entity/Feed.php b/core/modules/aggregator/src/Entity/Feed.php
index 3b14e8c24e367b4a2c0a93f0fe064d94f5f19e0e..e27450c7a2a9e7e57c73ef4872f40da5eccdaeb1 100644
--- a/core/modules/aggregator/src/Entity/Feed.php
+++ b/core/modules/aggregator/src/Entity/Feed.php
@@ -168,6 +168,7 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     $fields['refresh'] = BaseFieldDefinition::create('list_integer')
       ->setLabel(t('Update interval'))
       ->setDescription(t('The length of time between feed updates. Requires a correctly configured cron maintenance task.'))
+      ->setDefaultValue(3600)
       ->setSetting('unsigned', TRUE)
       ->setRequired(TRUE)
       ->setSetting('allowed_values', $period)
diff --git a/core/modules/aggregator/tests/src/Functional/Update/AggregatorUpdateTest.php b/core/modules/aggregator/tests/src/Functional/Update/AggregatorUpdateTest.php
index 9d659d018ac58f6bf0dee450b16c0f3f18010383..64bdb8e0181093522496c20257f1ae8435a97c1f 100644
--- a/core/modules/aggregator/tests/src/Functional/Update/AggregatorUpdateTest.php
+++ b/core/modules/aggregator/tests/src/Functional/Update/AggregatorUpdateTest.php
@@ -38,4 +38,21 @@ public function testSourceFeedRequired() {
     $this->assertTrue($field_definition->isRequired());
   }
 
+  /**
+   * Tests that the 'Update interval' field has a default value.
+   */
+  public function testUpdateIntervalDefaultValue() {
+    // Check that the 'refresh' field does not have a default value prior to the
+    // update.
+    $field_definition = \Drupal::entityDefinitionUpdateManager()->getFieldStorageDefinition('refresh', 'aggregator_feed');
+    $this->assertSame([], $field_definition->getDefaultValueLiteral());
+
+    // Run updates.
+    $this->runUpdates();
+
+    // Check that the 'refresh' has a default value now.
+    $field_definition = \Drupal::entityDefinitionUpdateManager()->getFieldStorageDefinition('refresh', 'aggregator_feed');
+    $this->assertSame([['value' => 3600]], $field_definition->getDefaultValueLiteral());
+  }
+
 }