diff --git a/lib/matplotlib/dates.py b/lib/matplotlib/dates.py
index 3c9a67e04a92..2712d64291a7 100644
--- a/lib/matplotlib/dates.py
+++ b/lib/matplotlib/dates.py
@@ -436,6 +436,10 @@ def date2num(d):
     For details see the module docstring.
     """
 
+    if hasattr(d, "values"):
+        # this unpacks pandas series or dataframes...
+        d = d.values
+
     if ((isinstance(d, np.ndarray) and np.issubdtype(d.dtype, np.datetime64))
             or isinstance(d, np.datetime64)):
         return _dt64_to_ordinalf(d)
diff --git a/lib/matplotlib/units.py b/lib/matplotlib/units.py
index b1140ded00b0..6e0a0b78d2a8 100644
--- a/lib/matplotlib/units.py
+++ b/lib/matplotlib/units.py
@@ -156,6 +156,10 @@ def get_converter(self, x):
         if classx is not None:
             converter = self.get(classx)
 
+        if converter is None and hasattr(x, "values"):
+            # this unpacks pandas series or dataframes...
+            x = x.values
+
         # If x is an array, look inside the array for data with units
         if isinstance(x, np.ndarray) and x.size:
             xravel = x.ravel()