well it was about Omnis ... have you reached there?
The 5am thing applies to all plantable stuff.
Thats when the game decides to age up all the plants by 1 day.
The game checks for conditions at around 5am in game.
Did you water the plant? Did you weed the plant? How strong is the fertiliser?
And in the case of plain Omni plants, what was fed to it?
That kind of things.
I once had a sim to harvest apples from apple trees but the garden was large so he couldnt harvest all of them by 5.
However after 5, the apple trees which have been harvested earlier on, grew another batch of apples.