Good to know about Crocuses
The Crocus genus consists of approximately 75 species, mainly growing wild in Southern Europe and the Middle East. It is one of the earliest to bloom in our gardens, right after winter aconite and snowdrops. Spring-flowering crocuses are divided into botanical crocuses, wild crocus species, and large-flowered crocuses. All crocuses thrive in ordinary garden soil and sandy soil, in sun and light shade under bushes and trees, and also in lawns and naturalized. Bees love crocuses. The botanical crocuses, which bloom earliest and reach a height of 5-10 cm, come in many colours and varieties within the species Crocus chrysanthus, Crocus sieberi, Crocus tommasinianus. They are followed by the large-flowered crocuses, which have larger flowers and are slightly taller, up to 15 cm. The third group of crocuses are autumn-flowering crocuses, autumn crocuses, or naked crocuses. They are planted in autumn and bloom immediately after in September-October. The leaves only appear in spring. In year 2, they will bloom slightly earlier than in the first year.
Large-flowered crocus, Crocus vernus and Crocus flavus
Large-flowered crocuses have larger flowers than botanical crocuses. They bloom in early spring, slightly later than botanical varieties. They come in vibrant colours: white, yellow, and blue-violet, as well as striped varieties. The most well-known are 'Jeanne d'Arc' (white), 'Mammouth'/'Yellow' (yellow), and the blue-violet varieties 'Flower Record' and 'Remembrance'. Their height is approximately 15 cm.
Botanical crocuses, Crocus chrysanthus, Crocus tommasinianus, Crocus sieberi
Botanical crocuses come in many colours and grow up to 10 cm tall. They bloom a week earlier than the large-flowered crocuses and are excellent for planting in lawns, for naturalizing, planting in beds, and in pots with other late-flowering bulbs such as narcissus and tulips.
Autumn-flowering crocuses, Crocus speciosus, Crocus zonatus (kotschyanus), Crocus sativus (saffron crocus)
Autumn-flowering crocuses should be planted immediately after purchase and will bloom shortly thereafter. The leaves do not emerge until spring. They grow to a height of 10 cm and come in light purple, lilac-pink, blue, and white.
Saffron crocus, Crocus sativus, is difficult to cultivate in Denmark. It will flower in the first year but is difficult to get to flower in year 2. Try growing it in a greenhouse. 800 stamens are needed for 1 gram of saffron, and there are 3 stamens in each flower. It originates from Iran and is also cultivated in Spain and North Africa, among other places.