Citrus Scab

What is it?

Citrus scab is a fungal disease caused by the fungus Elsinoe fawcettii. which is encouraged by cool, damp weather. Most citrus trees are susceptible to scab, but lemons can be particularly prone to it.

What does it do?

Scab affects the fruit, leaves, and branches of citrus trees. It causes slightly raised, irregular-looking ‘scabby’ growths. On leaves, they can also look like little raised, conical dimples. It can be grey or pinkish in colour at first and darkens with age.

Scab produces spores on its surface which can be spread very easily, carried by wind-driven rain or even the splash from regular watering.

Infection severity varies based on the volume of spores. It can appear relatively minor or nearly cover an entire fruit.

The inside of the fruit is unaffected and still fine to use, however scab can also cause fruit drop, depending on the time of infection, and it will gradually reduce the vigor of trees over time.

How do I fix this?!

Once scab is present on a tree, your best option is to cut off affected branches and dispose of them quickly and carefully so the spores don’t spread further. We’d suggest pruning on warm, dry days.

Keep a watchful eye on your trees, especially if weather patterns in your area are leaving your garden cool and damp for long periods. Catching scab early means you’ll have to prune less of your tree.

Other options include prevention. Copper fungicide sprays can be helpful as part of a regular care regimen, especially if you know your garden is prone to scab.

Yates Leaf Curl Copper Fungicide is one option, however as with any spray, you have to time your applications correctly and ensure you follow the directions carefully.