diff --git a/pydal/objects.py b/pydal/objects.py
index b50dda03a..caf151f97 100644
--- a/pydal/objects.py
+++ b/pydal/objects.py
@@ -2223,8 +2223,8 @@ def __init__(
 
     @staticmethod
     def _todate(value, regex=re.compile(r"^\d\d\d\d-\d\d-\d\d$")):
-        if value is None:
-            return value
+        if value in (None, ""):
+            return None
         if isinstance(value, datetime.date):
             value = value.isoformat()
         value = str(value)[:10]
@@ -2233,8 +2233,8 @@ def _todate(value, regex=re.compile(r"^\d\d\d\d-\d\d-\d\d$")):
 
     @staticmethod
     def _totime(value, regex=re.compile(r"^\d\d:\d\d:\d\d$")):
-        if value is None:
-            return value
+        if value in (None, ""):
+            return None
         if isinstance(value, datetime.time):
             value = str(value)
         value = f"{value}:00:00"[:8]
@@ -2243,8 +2243,8 @@ def _totime(value, regex=re.compile(r"^\d\d:\d\d:\d\d$")):
 
     @staticmethod
     def _todatetime(value, regex=re.compile(r"^\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d$")):
-        if value is None:
-            return value
+        if value in (None, ""):
+            return None
         if isinstance(value, (datetime.date, datetime.datetime)):
             value = str(value)
         value = value.replace("T", " ")