Cucumber Mosaic

Cucumber mosaic is a viral disease caused by the Cucumber mosaic cucumovirus (CMV). This disease has the widest global host range of any plant virus.


Spread by aphids,, it can also come into your garden on shoes, tools, and seeds. It occurs on all cucurbits except watermelon.

Cucumber mosaic leaf symptoms (Scot Nelson) Public Domain

Cucumber mosaic symptoms

Young infected leaves tend to cup downward. Mature leaves become severely mottled with light and dark green patches. Leaf midribs may become deformed with a zigzag growth. Due to the interference of photosynthesis, stunting and bumpy fruits may occur. Cucumber mosaic can also cause cucumbers to turn white.

Cucumber mosaic virus symptoms on fruit (William M. Brown Jr. - USDA Forest Service) CC BY 3.0

Cucumber mosaic controls

As prevalent as the mosaic virus is, planting resistant varieties is the best control. Once an outbreak occurs, all affected plants should be removed and thrown away. Reflective mulch can help repel aphid vectors. Chemical pesticides and insecticides have not been proven effective.