Four O'Clocks? I'm Confused

This is the east end of our house at nine in the morning.

Here is a closer view.  Once there were only pink and yellow flowers here but now there are salmon flowers as well.  Something going on with genetics?

This end of the house is now shaded by a fairly large walnut tree in the mornings.  When we moved here, it was sunny in the mornings.  The flowers were here when we moved in forty-five years ago.  I was pleased to see them.  They reminded me of the yard of the home where I grew up.  Mother always had Four O'Clocks.
As I remember, their name comes from their habit of blooming in the afternoon.  But now I wonder?  Am I remembering  correctly?  I thought they opened at four o'clock forty-five years ago.  Are they getting older and confused like the owners of the house?  Or does their habit of now opening at nine in the morning have something to do with when they get sun and when they get shade?

I could look up the answer using the Google Search Engine or I could just enjoy the mystery.

I hope all of you are having a pleasant day.  Come back again.