Alexandre Dumas 
Black Tulip 

Cornelius von Baerle, a respectable tulip-grower, lives only to cultivate the elusive black tulip and win a magnificent prize for its creation. But after his powerful godfather is assassinated, the unwitting Cornelius becomes caught up in deadly political intrigue and is falsely accused of high treason by a bitter rival. Condemned to life imprisonment, his only comfort is Rosa, the jailer’s beautiful daughter, and together they concoct a plan to grow the black tulip in secret. Dumas’ last major historical novel is a tale of romantic love, jealousy and obsession, interweaving historical events surrounding the brutal murders of two Dutch statesman in 1672 with the phenomenon of tulipomania that gripped seventeenth-century Holland. (Goodreads)