20 Jumbo Plus Saffron Crocus - Crocus Sativus Corms - 9 Cm 20 JUMBO PLUS Fresh Corms - 9 cm Late Fall blooming. Perennial. Jumbo Corms from Holland. Allow to dry out when dormant. Plant in Fall for Late Fall Bloom Sold by Marde Ross & Company, a Certified California Nursery since 1985.