Rust is a very common turf disease that can seem difficult to control and can lead to a frustrating fall. Controlling Rust begins with, understanding the conditions that favor its spread, and then implementing cultural practices that suppress it, and remove it from the turf.
What is Rust?
Rust is a fungal disease common to many cool-season turf grass. Perennial Ryegrass, Kentucky Blue, and Tall Fescues are all common turf varieties grown in northern climates. The fungus is easily identified in lawns as it begins to take on a brownish/red appearance. The Rust Fungus grows on the leaves and is easily rubbed off if you run your hand or fingers along the blades. Often, people will notice a reddish dust on their shoes or carpet after walking through it. Because it grows on the grass blades it will rarely kill the turf on its own, however, left unchecked, it can weaken the turf making it susceptible to more damaging conditions.
There are many chemical products that list Rust as a disease they will control. Over the years I have found most people achieve limited success with chemical treatments and I think there are many reasons why they do not work well.
- Systemic disease treatments control infectious diseases that damage the internal cells of plants. Because Rust grows on the outside of the plant they will not control or prevent Rust effectively. These treatments could still be applied to prevent the stressed areas from contracting other Just remember they won’t do much to the Rust itself.
- Topical treatments like Copper will be more effective, however, they still have some troubles. Watering the lawn regularly will wash off the treatment making reapplication necessary. You will also be regularly mowing the lawn, thus cutting off the treated areas.
Despite these difficulties with chemical controls, there are still many things we can do to control Rust in our lawns.
- As temperatures cool keep watering for as long as you have irrigation water available. However, take some time to adjust your sprinkler times in the shady areas of the lawn. Watering times for these areas should be reduced, to give them more time to dry out.
- Don’t stop feeding! Lawns that have not been fed during the summer months grow slowly. This slow growth and reduced temperatures will give rust more time to develop on the turf blades. Feeding with Zamzows Lawn Food in late summer/early Fall will keep the lawn growing at the proper speed to slow down the development of rust. Blades of grass that grow quickly will have more area to cut off removing Rust as it develops.
While Rust is a very annoying problem it is not a dire situation for your lawn. Changing up just a few things can limit its spread and reduce the time it is present in the lawn. I would rarely recommend using any of the chemical controls for Rust. You are better off focusing on the soil and cultural conditions in your lawn, which will improve the turf as a whole. If you have fertilized recently and still see Rust showing up, consider using some of Zamzows Compost Tea formula, or mixing up some Zamzows Thrive and treating the area to stimulate growth so your next mowing will remove it from the lawn.