Sant Jordi
One of the most important Catalan celebration is Saint George, 23rd April.
That day it's very common to see, in every corner, street, avenue... in everywhere, people selling roses, and in the main streets and avenues, like Las Ramblas, books stalls selling books, and in some places many writers talking with their readers and signing books.
The traditions says that all boys will offer a rose, usually red, to the girls and the girls will give back a book.
It's a love affair, or maybe it's our Saint Valentine's day.
In fact more than the 10% of the annual books acquisitions are made during this day.
In many schools they prepare for that day "Jocs Florals", which a writing competition, and during the day awards are given, usually the awards are flowers and books. 
Poetry is very popular, there's always a poetry category in the Jocs florals.