Hello Luc,
Thank you for writing.
I was able to see the "Start Date" text when I put the 1900-01-01 and "End Date" when I set the 2199-01-01 in the second DateTimePicker - please, refer to the attached video.
I have set the following properties for the controls:
Please, refer to my test project.
I hope this helps.
All the best,
Peter
the Telerik team