diff --git a/semantic_version/django_fields.py b/semantic_version/django_fields.py
index e5bd7eb..69f1e08 100644
--- a/semantic_version/django_fields.py
+++ b/semantic_version/django_fields.py
@@ -6,6 +6,7 @@
 
 import django
 from django.db import models
+from django.core.exceptions import ValidationError
 
 if django.VERSION >= (3, 0):
     # See https://docs.djangoproject.com/en/dev/releases/3.0/#features-deprecated-in-3-0
@@ -75,10 +76,13 @@ def to_python(self, value):
             return value
         if isinstance(value, base.Version):
             return value
-        if self.coerce:
-            return base.Version.coerce(value, partial=self.partial)
-        else:
-            return base.Version(value, partial=self.partial)
+        try:
+            if self.coerce:
+                return base.Version.coerce(value, partial=self.partial)
+            else:
+                return base.Version(value, partial=self.partial)
+        except ValueError as e:
+            raise ValidationError(self.default_error_messages['invalid'], code='invalid') from e
 
 
 class SpecField(SemVerField):
@@ -104,4 +108,7 @@ def to_python(self, value):
             return value
         if isinstance(value, base.BaseSpec):
             return value
-        return base.BaseSpec.parse(value, syntax=self.syntax)
+        try:
+            return base.BaseSpec.parse(value, syntax=self.syntax)
+        except ValueError as e:
+            raise ValidationError(self.default_error_messages['invalid'], code='invalid') from e