[C#] datetimepicker Mysql에 넣기

Mysql 필드형은 DateTime

dateTimePicker.Value.ToString("yyyyMMdd");

자동으로 변환되서 들어간다.

As stated in the title. 
I tried 

Convert.ToDateTime(dtpDate.Value.ToString())

but it is giving me an error that it is in incorrect format.
I also tried 

Date = String.Format("yyyy/MM/dd", dtpDate.Value.ToString())

but still no luck. I hope someone could help me.

Thanks.

&&&& birthEdit.Value.ToString("yyyyMMdd");