Crocus are perennial flowers that are rather short between 3″ to 6″ tall. One of the early bloomers in the Spring they have a buttercup shaped flower that is usually blue, purple, yellow, or white. While most Crocus bloom in early spring a few varieties are fall bloomers. Out of the 80 plus varieties of crocus about 30 are most commonly grown One of the most popular is the Dutch Crocus they are very hardy and have the biggest blooms.
Of the fall blooming varieties C. sativus is the sources of saffron the stamina is fine thread like flower parts that is collected and packaged. One other interesting fact is that while theses crocus bloom in the fall it is only the flower which appears, the foliage grows earlier in the year and then dies back.
Spring flowering crocus should be planted in the fall while the fall blooming varieties are planted in the late summer time. Crocus are planted by corms not bulbs and should be placed in large groups for the best displays. The corms should be planted in a sunny well drained location, that will not be disturbed. Planting depth is 3″ to 4″ about 5″ apart. The bottom of the corms is flat so that should be placed at the bottom of the hole. Crocus prefers a well drained soil that drys out quickly so keep this in mind when choosing your location. If you plant them in a bed that will receives a lot of water over the summer chances are they will rot. They are perfect for rock gardens. When planting crocus you should try and find a place that will not be disturbed and one which marauding herds of squirrels and other small animals will not dig them up. If the weather is dry you should water occasionally up until the first snow fall. If you do not have snow then water periodically throughout the winter.
Crocus can be forced indoors as well for blooms in the winter. Choose a pot that has large drainage holes and fill the bottom with gravel. Add good clean potting mix to within 2″ of the top. Place the corms in the pot 1″ apart pushing them down into the soil an inch or so then add more soil to about a half an inch from the top of the pot.Water the pots well and then let the water drain out. Place your pots in a cool dark place and maintain a temperature between 45 to 48 degrees for six weeks. Check your pots once a week and look for roots growing out of the drain holes. Once the roots have established themselves you should move them into a sunny room and in about three weeks you should be enjoying your crocus blooms.