Most of us think of crocus as a harbinger of spring but there are fall blooming species as well. One of these fall bloomers is Crocus sativus, whose girly bits are the source of saffron. The saffron crocus is a pretty purple thing with long red/orange styles and stigmas. There are other saffron crocus species as well but C. sativus is the most well known. One discussion on the Pacific Bulb Society mailing list
stated “The saffron series of crocuses, as given by Mathew, includes eight species: pallasii, C. thomasii, C. artwrightianus, C. sativus, C. moabiticus, C. oreocreticus, C asumaniae and C. hadriaticus. “

Corms can be purchased commercially for a bit under $1 each. They should be planted in the early fall for a first harvest in 4 to 6 weeks. Like all crocus they are perennial and need a temperate climate. They will increase in mass over time if planted in a favorable location. Many sources discuss how difficult it is to actually get productive blooms from Crocus sativus. It is said to be sterile and is only reproduced vegetatively. Many critters like to eat the corms.

Stigmas and styles (the female parts of the flower) are about the size of a bit of thread. It takes a lot of them to produce much saffron. Each flower produces three. Cultivation and harvest is very labor intensive. Flowering is unreliable. These are some of the reasons that saffron is the most expensive per pound spice around.

A home gardener can theoretically grow and harvest saffron. Be sure you are getting Crocus sativus, not one of the other purple autumn blooming crocus. I sadly have a lovely fall crocus crop but they are not C. sativus. One of these days I plan to remedy that situation.

Tips I’ve read on growing Crocus sativus:
Divide frequently
Replant the larger corms for a crop; grow the smaller ones on in a nursery bed
Plant in mesh containers to prevent predation
Plant deeply, maybe as deep as 8 inches
Rotate locations
Treat like a crop not an ornamental
Harvest the entire flower in early morning, later open flower to remove style and stigma
(Note crocus flowers open widely in the sun but are closed in early morning)
Heat treat the harvest to prevent mould.

Source of the quote:

For the quest...
FloraQuest 2011: If We Cantelope, Lettuce Marry!