Common Lilac.

We have a lot of Lilacs in our garden, both lilac and white.
The flowers of the Lilac has most of the time four petals, some have five petals. I've been told if you find a flower with five petals you shall pick that little flower and swallow it! It will bring you luck!

Some people believe in superstition. In former times people believed that a person who was born between eleven o'clock in the evening and midnight was able to see ghosts in the flowering lilac at sundays just between eleven o'clock and midnight.

Knock on wood, I'm glad I'm not superstitious.

Superstitious makes me think about Stevie Wonder's song "Superstition" from 1972.