advstringgrid edDateEdit

I'm using edDateEdit in a stringgrid to pick dates.

The grid is programatically filled from data in a database.  If the DB date field is NULL, the grid cell is filled with empty quotes.
I can't the datetimepicker in the grid to set the selected date, unless I press enter after picking the date. (Only when the field was originally empty.) Upon saving the grid back to the database, the selected date is not entered, only the current date - which I know is what I'm artificially setting to prevent the datetime picker from erroring on editing.
in the geteditortype for the grid in question, I'm handling the empty cell as follows:

procedure TfrmBooze.grdBoozeGetEditorType(Sender: TObject; ACol, ARow: Integer;
  var AEditor: TEditorType);
  i : integer;
  with grdBooze do
    if ACol in [7] then
      if grdBooze.Cells[grdBooze.Selection.Right, grdBooze.Selection.Top] = ' ' then
        grdBooze.Cells[grdBooze.Selection.Right, grdBooze.Selection.Top] := datetostr(tdatetime(date));
      AEditor := edDateEdit; := grdBooze.DateTimePicker.Date;

The correct way to preset text for a cell and override to edit the default cell value  is via OnGetEditText: