In Genesis, can you explain the photosynthesis paradox?

I'm reading the Bible and I'm already stuck at Genesis 1. When God separated light and dark on Day 1, I'm surprised to read he waited until Day 4 to make the Sun, AFTER he made plants on Day 3. God made plants to require sunlight and regular periods of light and dark (day and night = Day 4) or else they die. I'm just saying the sequence seems as if whoever wrote the Bible didn't understand natural processes very well. I'm sure there's an excuse for this apparent paradox, right?