Rust is reddish brown dust that appears on your grass blades and may be present June to October. Rust is caused by drought as well as nitrogen deficiency.
To treat this disease a high nitrogen fertilizer needs to be applied. First and foremost, watering deeply but less frequently will allow the roots of your grass to deepen and your lawn will be able to repair itself quickly from the disease. One inch of water once a week between 4am to 7am is crucial to maintain active growth. Increase watering frequency during extreme heat conditions. Proper mowing is also very important, you should never cut more than 1/3 of the grass blade off at any time to avoid shocking the grass plant. Keep your lawn around 3” long to make sure your grass doesn’t start using its food reserves, which will impact how quickly it recovers.