Crocus flower bulbs - harvesting, drying and storage, dealing with pests

Saffron flowers are picked manually early in the morning, when it is still closed to obtain better quality saffron. Otherwise stigmas lose their colour and quality deteriorates. Separation of the stigma from the flower is called “stripping or peeling” and it is always done by hand. During peeling, avoid taking any part of the yellowish style as this degrades the quality of the product. After separating the stigma from the flower, it is essential to dry them.

Incomplete drying results in loss of the stigma due to decomposition. Stigma can be dried in an oven warmed room at temperature 30-35 o c for 10-12 hours. Around 75 kg of fresh flowers are needed for 1 kg of fresh stigma and approximately 1400-1500 flowers are needed to obtain 1gm of dry stigmas because there is a weight loss of 4/5 during the drying process. Dried stigma should be stored in tightly sealed glass jars or cans because saffron filament is extremely hygroscopic and susceptible to fermentation which results in a change of colour and unpleasant odour.

Harvesting and Storage of corms

Corms are lifted at the beginning of the summer after complete senescence of the aerial parts. The most common uprooting method is manual by means of a hoe or small plough. During lifting it is important that the bulbs are handled gently to avoid damage. After lifting, bulbs should be checked for possible defects like rot, bruises or insect attack and remove the remains of mother bulbs, roots and old stem. Before storage, treat the bulb with fungicide and dry in partial shade. The corms are stored in a cool, dry place for a minimum of 2 months duration.

Diseases, Pest and Physiological Disorder
The most serious fungal disease of saffron is Rhizoctonia crocosum which causes corm decay. Other diseases which may affect the crocus are blue mould, Penicillium spp, gladiolus dry rot, hard rot, scab, hyacinth black slim, narcissus basal rot and tulip grey bulb rot.

Control measures include removal and burning of the infected plants, adoption of crop rotation, drenching infected plants with fungicide like Bavistin @ 2.0 gm per litre. Other measures to prevent infections are careful handling, avoid mechanical injury and store in cool, dry & well ventilated conditions.

Pests like rats, moles may cause severe damages to saffron plantations, which feed on corms. It can be effectively controlled by using poisonous bait. Sometimes rabbits and pheasants may dig up and eat the corms; squirrels may eat the emerging shoots. To prevent the losses, cover the plantings within fine mesh cages.

Insects like yellow or light brown wingless tulip bulb aphids may infest corms during storage and persist to form colonies, which damage young shoots. It can be controlled by fumigation of insecticide in storage.

Physiological Disorder

The most common physiological disorder in crocus is known as chalking. In this corm become dry and hard in storage, while scales are white, opaque and chalk like when broken. Usually it occurs due to mechanical or sunscald injury to the bulb just after lifting and aggravated by poor ventilation and high humidity in store. It is advisable to improve bulb handling and storage technique.

Another physiological disorder in crocus is flower abortion which can occur due to inadequate cooling, excessive temperatures during forcing or improper cultivar selection for forcing.

Variety, Various colours in Crocus:

Garden crocus or Dutch crocus (C. vernus)

White – Joan of Arc, Schneestrum, Kathleen Parlow.

Lilac Blue- Queen of the blues, Excelsior.

Lilac- Vanguard, Haarlem Gem.

Violet –striped- King of the Stripes, Pick wick, Paulus Potter, Striped Beauty.

Purple- Enchantress, Remembrance, Purpureus Grandiflorus.

Wild species:


Golden yellow- Golden Bunch, Gipsy Girl, Zwanenburg- Bronze,

White to pale purple- Blue Bird, Blue Pearl, Advance.

Purple –Blue- Blue Peter.

Blue- Lady Killer,Zenith

Lilac- Barr’s Purple, Taplow Ruby, Whitewell Purple.

Violet- Elegance,

White- Snow Bunting, Snow White, Albus.

Saffron-C. sativus

Yellow- Brassband, Cream Beauty(Cream)