Some late-blooming crocus varieties planted around the yard can transform autumn into a second spring, providing a welcome burst of color as other flowers fade and the leaves begin to fall.
Nurseries generally label them “minor bulbs,” however, stocking only a few if any because there is so little demand.
There are fall crocuses — some 30 species — and then there are 15 or so colchicum. There is a great deal of difference between the underused lookalikes. Fall crocuses are planted in early September, and bloom four to five weeks later. They do not bloom in the spring, said Richard Jauron, a horticulturist with Iowa State University Extension.
A colchicum has six stamens, those pollen-laden spikes inside the blooms, while a crocus has three. Colchicum bulbs are poisonous and are not eaten by plant predators. The bulb-like corms of crocus are not, however, and are popular fare for foraging deer, voles, and chipmunks.
Crocus is a member of the iris family and develops from corms, an elongated, starch-containing growth on the plant stem from which a shoot forms. Colchicum is related to lilies and grows from bulbs.
Both bloom in late September and October in USDA zones 5 through 9 — northwest Ohio is Zone 5 — zone 4 too if planted in protected locations.