diff --git a/mappers/date.inc b/mappers/date.inc
index 1616084..6892bf7 100644
--- a/mappers/date.inc
+++ b/mappers/date.inc
@@ -83,6 +83,15 @@ function date_feeds_set_target(FeedsSource $source, $entity, $target, array $val
 
       $field[$language][$delta][$value_key] = $value->format($format, TRUE);
       $field[$language][$delta][$offset_key] = $value->getOffset();
+
+      // Ensure that both value keys always exist to prevent php notices in
+      // date_field_validate().
+      if (!array_key_exists('value', $field[$language][$delta])) {
+        $field[$language][$delta]['value'] = NULL;
+      }
+      if (!array_key_exists('value2', $field[$language][$delta])) {
+        $field[$language][$delta]['value2'] = NULL;
+      }
     }
 
     $delta++;