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Rust is a fungus problem that can affect nearly every green and leafing plant. It’s descriptive, rusty name comes from the reddish, brownish or yellowish color that it causes the leaves to turn, and also for the spores that appear powdery and will rub off on anything that touches the affected leaves and will spread on the slightest air current. Controlling rust and curing plants affected is simple.
Remove Infected Leaves and Stalks
Remove leaves on plants that are infected immediately. If rust infects your turf grass, regular mowing with a bag-style mower will help to do this. Prune away infected plant stalks as soon as the plant has finished its blooming cycle. Never compost this infected organic material. Composting infected organic material can cause it to infect the resulting mulch and loam. Instead, burn the infected plant leaves and stalks to control the spread of the fungus.
Use Sulfur and Fungicides
Use sulfur or other fungicides to kill the surface spores and clamp down on the spread of the infection to other plants. Plants should be treated every 10 days with fungicide. According to Drs. Buck and Williams-Woodward at the University of Georgia, you should change the fungicide that you use periodically to prevent rust from developing a tolerance to it. Sulfur used on a lawn will also help repel insects such as mosquitoes and ticks, but must be reapplied after each rain.
Adopt Preventative Measures
You can stop the spread of rust and help to bolster rust-infected plants by increasing the overall “hygiene” of a plant. Rust is a problem in areas where plants are exposed to moisture for long periods of time, such as hot, humid areas where dew does not dry. Increasing air circulation around and through a plant will help it to dry faster and create conditions where rust cannot thrive. To do this, space plants such as day lilies, roses and fruit trees and bushes farther apart when planting. Additionally, prune plants such as roses and fruit trees and bushes so that air can pass through their center mass more easily. Finally, adding organic fertilizer such as compost or liquid fertilizer in the plant’s water system will help to make a plant healthier. Healthier plants will be able to resist infections of rust and other fungus more effectively than unhealthy plants in the same way that people who take their vitamins are more resistant to the common cold.