What does it mean if an author's writing is too flowery?

When you use a daffodil as a pencil

Flowery writing is writing that is overly descriptive, fancy, ornate, and so on. It doesn't add to the narrative; it tries to hard to be poetic.

Usually just means the author is being too classic or elegant when such writing doesn't necessarily require it. In other words, the author expresses the book in a romanticized way which takes away the enjoyment of reading.

hope that helps :)

It can mean when you use to many adjectives in your use to describe or HOW you use them (& like Jester already said... I agree, & yes- too ornate).

He wore a pale pink puffy plumed perfectly pleated peacoat made precisely for his persnickety peacock personality. ('And I could have mixed it up with any other letters - or we get too descript. For further example: J.R.R. Tolkien could be accused of that writing style, which I rather like and prefer....)