Margaritas a los chanchos - Pearls before swine

Ahora saben por qué era que no había que tirarles margaritas. Se ponen melancólicos.

The Spanish equivalent to the phrase "to cast pearls before swine" is "tirarle margaritas a los chanchos", which has the same meaning but its literal translation would be "throw daisies to the pigs".
The problem is that then the pigs get melancholic.