Treating Rust Spots on Cucumber Leaves

Treating Rust Spots on Cucumber Leaves

Rust-colored spots spreading rapidly across cucumber leaves indicate a fungal disease, typically encouraged by damp, humid conditions. While the plants may still produce fruit, the disease can weaken them and reduce yields.

Control Measures

Apply a copper-based fungicide, available at most nurseries and garden centers. Follow the label instructions for application rates and frequency. Copper fungicides are effective against many fungal leaf spots and are suitable for organic gardening when used as directed.

To prevent future outbreaks, improve air circulation by spacing plants properly, water at the base of plants (avoid wetting foliage), and mulch to reduce soil splash.