OP,
I am not sure what level of photoshop experience you have, but with still life and other photography, its all about manipulating light, or in terms of PS, is about light and dark.
Know or learn un-destructive editing, color management, how to set the desired look and feel of an image. When you become very competent, you can turn night into day and vs.... if that is what you so desire to do.
Invest a lot of time, even after 10-15 years, there is still lots to learn - which is what makes it so interesting and fun to do ;-)
Let us know if you have any more specific questions
Henrik