DateTimePicker - Values to blank when screen is opened, in C# VS2010, .NEt..

Question

   What I have is a Window.NET application with many date fields on it.  Sometimes I will not want to update every date field on the screen, but everytime time I update the DB is stores the dates.  What I did was to initiate the fields to a blank and this works, except for one thing.  When I  pick the date field that I want to update and click on the date it returns a blank field back and it just so happens to update the DB, but I never saw the date in the datetimepicker box.
 What I would like to do is this.  Bring screen up with blank values in the date boxes, then choose the field that I want to update, click on date, date shows up in box, then I update the DB with that value, but the other date fields that I didn't choose I want them not to anything.

I would appreciate the help.  This is the last thing I need to correct and I will be finished with my first project.


Thanks,
Ben