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 snowdrop. 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 areas. Bees love crocuses. The botanical crocuses, which bloom earliest and reach a height of 5-10 cm, come in many colors 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, meadow saffron, or naked-flowered crocuses. They are planted in autumn and bloom immediately afterward in September-October. The leaves do not appear until spring. In year 2, they will bloom a little earlier than in the first year.
Large-flowered crocus, Crocus vernus and Crocus flavus
Large-flowered crocuses have bigger flowers than botanical crocuses. They bloom in early spring, slightly later than the botanical ones. They have strong colours, white, yellow, and blue-purple, and striped varieties. The most well-known are 'Jeanne d'Arc' (white), 'Mammouth'/'Yellow' (yellow), and the blue-purple varieties 'Flower Record' and 'Remembrance'. The 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 high. They bloom a week earlier than 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 narcissi and tulips.
Autumn-flowering crocuses, Crocus speciosus, Crocus zonatus (kotschyanus), Crocus sativus (saffron crocus)
Autumn-flowering crocus should be planted immediately after purchase and will bloom straight away. The leaves only appear in spring. The height is 10 cm and the colour is light purple, purple-pink, blue, and white.
Saffron crocus, Crocus sativus, is difficult to grow in Denmark. It will bloom the first year, but it is difficult to get it to bloom in year 2. Try it in a greenhouse. 800 stamens are needed for 1 gram of saffron, and there are 3 in each flower. It originates from Iran and is also grown in Spain and North Africa, among other places.