Cyclamen Diseases

Cyclamen Diseases
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Please call us at 831-755-0570 if you have any disease or pest problems. We would like to assist you on improving your Cyclamen quality.

The following information has been compiled from our experience growing Cyclamen in Central California. Your regional diseases and control techniques may vary.

Fusarium Wilt: Rapid yellowing, wilting and death that often occurs on one side of the plant. The corm may appear brown in parts, or there may be red or purpling ring of discoloration inside the corm. This occurs mainly during warm humid times of the year. Strict sanitation is essential. remove and destroy all infected plants. Subdue or Cleary's drenches help control but will not eradicate. Many growers use preventive fungicide routines beginning at the week 5 stage.


*A Fusarium infected plant leaves turn yellow. One section of the plant withers. Even though it is infected the plant continues to grow.*	Common appearence of Fuarium infected Cyclamen.	Tubers must be sliced open to identify Fusarium infection. The vascular bundles of this tuber are infected. Indicated by the orange/brown color. The infected spots allow for the easy growth of fungi and bacteria. Either the top or bottom of the tuber can be infected.

Erwinia Soft Rot: Sudden wilting followed by plant collapse. The corm appears slimy and there mat be an odor from the infected corm. Warm and humid weather encourages rapid rot. Provide sufficient spacing and avoid splashing water. Remove and destroy infected plants. Since there is no chemical control for this disease, good greenhouse sanitation and cultural techniques become vital means of control.


*The bacteria disease Erwinia, clogs the leaf and flower stems and prevents any fertilizer and water from entering the plant.*	The weak soft corm is brown inside.	*The leaf and flower stems are soft on the bottom and turn black/brown. The corm is turning black inside.*

Botrytis: Soft decay of flowers and leaves, spotting on flowers and a presence of downy gray mold. Commonly 1/4 to 1/2 of the plant will wilt after Botrytis cankers have girdled a number of leaf stalks. occurs in areas of high humidity, poor air circulation, crowded plants and cool night temperatures. Provide aeration, individual tube watering, bottom heat and other means of keeping the plant's surface dry. Fungicides may be beneficial.


On the wet, brown leaf and flower stems develops a fungi of grey spores.	*Flowers show blotches created by Botrytis.*	Flower blotches are 2 - 3 mm long with dieback in the center.

Cylindrocarpon: Soil fungi which attack cyclamen at all stages. It causes a slowing of growth and flowering. Cylindrocarpon causes symptoms in the plant above ground: rotting of mature leaves and cell death in the bulb. Poor drainage, excessive watering and compressed soil mixes help the fungus to develop. Chemical control is not easy. It can be confused with Fusarium and Colletotrichum.

Collectotrichum (Gloeosporium):A soil fungus that causes anthracnose in cyclamen. The fungus attacks the center of the plant. Young buds and leaves wither at the tip. Stalks swell like bottles. Circulation in the plant is blocked causing mature leaves to enlarge. Mild temperatures and high humidity encourage the growth of spores and the spread of disease. Chemical controls are available for prevention and treatment. Winged insects spread the disease and must be controlled.