Jennifer Schultz Nelson
Extension Educator, Horticulture
I've been prowling my yard looking for signs of spring. Right on schedule, the crocuses are showing themselves and appear in a hurry to be the first to bloom.
It may surprise you that as a genus, Crocus is in the iris family. But unlike iris, Crocuses grow from a corm, which is technically compressed stem tissue. It is not uncommon to hear Crocus referred to as a bulb, though technically this is incorrect. In everyday discussions they are typically lumped in with other spring blooming flowers that really are bulbs.
Crocuses are native to central and southern Europe, North Africa and the Middle East, across central Asia to western China. But they have made themselves at home in many North American gardens.
Much of the cultivation of Crocus commonly grown today is credited to the Dutch. Their first experimentations with Crocus date back to the 1560's, and by the 1620's there were new garden varieties developed.
Sixty years to develop a new plant? You've got to be kidding! But it's no joke. Plant breeders hybridizing Crocus, or any other bulb or bulb-like plant must be very patient people. They must make a cross of two flowers, wait for seed to develop, germinate that seed, then wait years for that bulb to grow large enough to flower before they can select flowers for their next cross.
There are about 80 known Crocus species, and around 30 are grown cultivated as garden plants. All share similar appearances, with cup-shaped solitary flowers that taper at the bottom. The flower colors seen vary widely in shade, but tend to be lilac, mauve, yellow, and white, and sometimes striped.
The foliage of Crocuses are nondescript, almost grass-like, usually with a stripe of white down the center. Typically the foliage emerges first, and the flower is borne in the center.
Every Crocus flower contains three thread-like stamens, the male portion of the flower. The stamens of the fall-blooming crocus, Crocus sativus, are the source of the ultra-expensive spice saffron.
Unfortunately, to have a good show of crocus this spring, you had to have planned ahead by planting the previous fall. As with most spring blooming bulbs, crocus need a cold period during winter to flower in the spring.
Though most Crocus grown in North American gardens are considered to be perennials, a late frost or snowfall in the Spring may kill Crocus.
They also need a well-drained planting location. Soils that hold a lot of water and don't drain well are generally not conducive to growing bulbs well. Excessive water is an engraved invitation for fungus to move in and rot your bulbs.
Most cultivated spring-blooming Crocus bloom early enough in the season that they have bloomed and their foliage has yellowed by the time the garden really wakes entirely from the winter. This makes Crocus a great choice for naturalizing in the lawn, or in planting beds where other perennials will steal the show later in the season.
Like other spring-blooming bulbs, it is essential for the foliage of Crocus to remain intact after the blooms have faded to capture the sun's energy to power next year's blooms. But unlike other spring bulbs, Crocus' foliage is not as obtrusive as other species. The foliage is very narrow and fine to begin with, and persists after the blooms for a relatively short time.
A big reason I chose crocus to plant in my yard, besides the obvious fact that I like them, is that many reputable sources consider them to be deer and rabbit resistant. But their inclusion on the "resistant list" appears to vary considerably by location. Some sources I found rated them as susceptible as the "filet mignon" of bulbs, tulips.
This illustrates the point that no plant is deer and rabbit "proof". Unfortunately, they don't read our books and know that they "don't" eat a particular plant if they are really hungry and food sources are slim.
So far the deer and rabbits haven't wreaked havoc on the Crocus in my yard. Other plants have not fared so well. Hopefully the wildlife and I can call a truce and peacefully coexist and enjoy Spring as it unfolds.