Lawn Rust in Idaho

Lawn Rust in Idaho

This week's customer question:

“Hi, what would you recommend for getting rid of lawn rust? I read it can be due to soil that is low in nitrogen. We've used the Zamzows Lawn Program for the past two years and continue to get the lawn rust in late summer/early fall. Thanks for any assistance you can give!”

In fall, lawn rust becomes a frequent issue for many homeowners in the Treasure Valley. Lawn rust will rarely cause any long-term damage to the lawn. It does make for an un-welcome mess you need to clean up at the end of your mowing. 

Identifying Lawn Rust

Lawn rust appears on the grass blade tips as an orange powder stuck to the leaves. You want to make this distinction, as brown or dying leaf blades may be symptomatic of other issues in the lawn. You will often notice rust for the first time after walking through your grass and find your shoes covered in the orange spores. You can also run your hand across the grass, or run your fingers along the leaf blade, removing the rust from the blades, onto your hand or fingers.  

What Causes Lawn Rust?

There are several contributing factors to the appearance of lawn rust. Most often, summer stress, mowing too low, low nitrogen levels, and watering at night will contribute. Lawn rust commonly occurs in late-summer through early-fall, and in mid-spring. Rust begins to show up when temperatures range from 60-85 degrees Fahrenheit, along with the presence of water. 

Ways to Control Lawn Rust.

The best thing you can do to begin combating rust in your lawn is to fertilize with Zamzows Lawn Food. Your lawn is under a tremendous amount of stress during the hot summer months, and feeding is the number one course of action to relieve stress and encourage new growth. As the lawn grows, you will be able to remove most of the rust as you mow, reducing the need for chemical controls. 

Reducing your watering will help the lawn dry out. We regularly forget to reduce the amount of water our grass gets as we head into fall. With lower temperatures, the water demand on our lawn is reduced by half almost overnight. Remember, your lawn only needs one inch of water a week, and the amount of evaporation and transpiration goes down exponentially with the temperature. You should also avoid watering at night. Mid to late mornings are always the best times to water, to assure the lawn has an adequate amount of time to dry out before the sun goes down. 

October is also the time of year where I begin to lower my mower height. Make it a habit to step your mower down one notch each week. Doing this accomplishes a few crucial tasks. First, you are removing any rust that is growing on the grass tips. Second, you want your lawn to be about 2 inches for your last mowing. Reducing it to this height all at once will cause a lot of damage so, you want to do it slowly over a few weeks. Lastly, it helps clean up any damaged/dead blades in the lawn and helps clean up a little thatch. 

Several fungicides include rust on the label. Generally, I have found them to be inconsistent at best when it comes to controlling lawn rust. Zamzows DefendZ Disease control is a granular systemic that will protect new blades as they come in. We also carry a newer bio-fungicide called Revitalize that should control rust very well, and Revitalize is organic!

So, when it comes to lawn rust, it is best to look first to your cultural practices. Make sure the lawn is fed, reduce your watering, and reduce your mowing height. These three practices will help you control most of your rust issues.