diff --git a/tests/model_forms/tests.py b/tests/model_forms/tests.py
index f03c80f..4c13740 100644
--- a/tests/model_forms/tests.py
+++ b/tests/model_forms/tests.py
@@ -549,6 +549,19 @@ class ModelFormBaseTest(TestCase):
         self.assertEqual(list(OrderFields2.base_fields),
                          ['slug', 'name'])
 
+    def test_default_populated_on_optional_field(self):
+        class PubForm(forms.ModelForm):
+            mode = forms.CharField(max_length=255, required=False)
+
+            class Meta:
+                model = PublicationDefaults
+                fields = ('mode',)
+
+        mf = PubForm({})
+        self.assertEqual(mf.errors, {})
+        m = mf.save(commit=False)
+        self.assertEqual(m.mode, 'di')  # from the model field default
+
 
 class FieldOverridesByFormMetaForm(forms.ModelForm):
     class Meta: