How and why do some flowers only grow at night?

Question

I cannot find an answer to this question and I would really appreciate an answer please. :)

Answer 1

The flowers which bloom during night are usually pollinated by insects which are nocturnal ( moving during night time only).  These flowers are white in colour ( to make them seen by the insects)  and have strong fragrance ( which can attract the insects even the flowers are not visible to the insects). Some of the species may get pollinated by wind also.