It affects leek, garlic, onion, and chives, and usually appears as bright orange spots on infected plants.

[2] According to the Royal Horticultural Society, there are no fungicides approved for use by amateur gardeners to combat leek rust.

[5] On leeks, P. porri manifests as bright orange or yellow pustules on the upper parts of the leaves, usually between veins.

[2] An infected leek's discolouring can cause it to lose market value, as there is an expectation the vegetables do not have visual defects or flaws.

In addition, Uma (1984) writes that P. porri has caused significant losses for garlic farmers in California, Israel, South Africa, and Brazil.