Crocus is a genus in the iris family of plants, Iridaceae. Usually, they adapt to colder weather you can plant them in all areas. They usually are very early bloomers, after the snow is melted. Nothing says that spring is arriving, like crocus flowers.
Crocus is a perennial which grows from corms. A corm is similar to a bulb but the primary storage tissue is the stem, not the leaf tissue. Besides Crocus, Gladioli and Crocosmia are from corms.
There are very well-known Crocuses. If you are familiar with the spice called Saffron, it is the stigma of a Crocus flower, called Crocus sativus. This is an autumn flowering Crocus. Yes, there are species that bloom in summer or autumn. Crocuses are native to woodland, meadows from sea level to mountains, mostly in the Middle East, North Africa, and East to China.
The name is derived from Greek Krokos which in itself is derived from Semitic and Arabic words of Kurkum meaning Saffron! It was introduced in the Netherlands where bulbous flowers are very popular for cultivation was around 1560. There are more than 90 species of Crocus.
Crocus leaves are grass-like and appear with, after, or before the flower. Some species bloom from August to October. Crocuses are usually 3 to 6 inches tall and come in white, yellow, and shades of purple or pink. Saffron used in cooking comes from Crocus flowers. Crocus sativus which blooms in autumn has purple flowers. Crocus vernus or as known Dutch Crocus comes in various shades and blooms from February to April and is probably one of the most popular varieties grown in gardens or pots.
How to grow Crocus:
Plant them in sun or partial shade in any type of soil but well-drained. Usually, they should be planted in late fall, they look beautiful around mature trees or in grass but make sure they do get enough sunlight.
Place the corms about 3″ or 7.5cm deep and apart. and plant them in a group for both color and natural look. If you notice that mice or other pests are vulnerable then you can add some eggshells or oyster shells to the soil mix to deter them. Crocuses will propagate naturally. Crocuses are not susceptible to disease however mice and squirrels do feed on corms!
You can force Crocuses to bloom at any time in pots you need to chill the pots to about 40°F in a dark room for about 8 weeks with moderate watering, make sure it is well-drained. Then bring them to a warmer temperature and they will bloom. But you can’t transplant them outdoors, they are spent.