Which poem read by mother?

Hmm. According to her dialogue, at least, she wrote it herself...so I'd assume it was written by Pedro Almodovàr, for what it's worth.

In The Pedro Almodóvar Archieves, he quotes, "and Chus recites as they are arriving in Almagro "My Village," a poem my mother still recites."

Hope this helps a little bit.