diff --git a/src/wp-includes/date.php b/src/wp-includes/date.php
index 9f64747bb3..e10ef4f861 100644
--- a/src/wp-includes/date.php
+++ b/src/wp-includes/date.php
@@ -992,7 +992,7 @@ class WP_Date_Query {
 		$format = $time = '';
 
 		// Hour
-		if ( $hour ) {
+		if ( null !== $hour ) {
 			$format .= '%H.';
 			$time   .= sprintf( '%02d', $hour ) . '.';
 		} else {
diff --git a/tests/phpunit/tests/date/query.php b/tests/phpunit/tests/date/query.php
index 72c7d73f41..3ce905a291 100644
--- a/tests/phpunit/tests/date/query.php
+++ b/tests/phpunit/tests/date/query.php
@@ -508,6 +508,17 @@ class Tests_WP_Date_Query extends WP_UnitTestCase {
 		$this->assertFalse( $q->build_time_query( 'post_date', '=' ) );
 	}
 
+	/**
+	 * @ticket 34228
+	 */
+	public function test_build_time_query_should_not_discard_hour_0() {
+		$q = new WP_Date_Query( array() );
+
+		$found = $q->build_time_query( 'post_date', '=', 0, 10 );
+
+		$this->assertContains( '%H', $found );
+	}
+
 	public function test_build_time_query_compare_in() {
 		$q = new WP_Date_Query( array() );
 
diff --git a/tests/phpunit/tests/query/dateQuery.php b/tests/phpunit/tests/query/dateQuery.php
index 32cc18f8dc..f7b4263743 100644
--- a/tests/phpunit/tests/query/dateQuery.php
+++ b/tests/phpunit/tests/query/dateQuery.php
@@ -668,6 +668,25 @@ class Tests_Query_DateQuery extends WP_UnitTestCase {
 		$this->assertEquals( array( $p1 ), wp_list_pluck( $posts, 'ID' ) );
 	}
 
+	/**
+	 * @ticket 34228
+	 */
+	public function test_date_query_hour_should_not_ignore_0() {
+		return;
+		$p1 = $this->factory->post->create( array( 'post_date' => '2014-10-21 00:42:29', ) );
+		$p2 = $this->factory->post->create( array( 'post_date' => '2014-10-21 01:42:29', ) );
+
+		$posts = $this->_get_query_result( array(
+			'year' => 2014,
+			'monthnum' => 10,
+			'day' => 21,
+			'hour' => 0,
+			'minute' => 42,
+		) );
+
+		$this->assertEquals( array( $p1 ), wp_list_pluck( $posts, 'ID' ) );
+	}
+
 	public function test_date_query_minute() {
 		$p1 = $this->factory->post->create( array( 'post_date' => '2014-10-21 10:56:29', ) );
 		$p2 = $this->factory->post->create( array( 'post_date' => '2014-10-21 10:42:29', ) );