Orange spots on grass? Its Lawn Rust.


Orange spots on grass? Its Lawn Rust.

Orange Spots on Grass. Its Lawn Rust

Notice weird orange or yellow (rust colored) spots on your grass? Its dusty, it gets all over your shoes, and it will make your think your lawn is dying. Well, its a disease called lawn rust. 

It can effect all types of lawns, from warm season zoysia and bermuda lawns, to cool season fescue and bluegrass.

What is Lawn Rust?


Lawn rust is an orange or rust colored powdery fungus that will grow on your lawn. It is obvious how it gets is name, the rust color. All that orange stuff is actually spores from a fungus.

The rust shows up when your grass is growing slower than usual, combined with cooler temps at night (temps in the 70's) and humid or wet nights (i.e. cool with lots of dew).


Rust will most likely show up in shady areas first, since those areas stay cooler and wetter. From there, the rust can spread fairly quickly. Just kick it once with your shoes, or mow the grass, and watch the dusty spores spread to other areas of the lawn! Hence, the spores in your lawn could have come from anywhere the wind blew, or you and your dog walked.

What does it do to my lawn?


Lawn rust on Zeon Zoysia Grass
Lawn rust is not initially detrimental to your lawn's health. However, the spores from lawn rust will cover the grass blades, thus weakening its ability to perform photosynthesis (gives plants energy), thus making the grass weak. If the grass gets too weak, it can die off, so it is a great idea to go ahead and take care of lawn rust as soon as possible.

Rust can easily damage a lawn if not cared for quickly, as it spreads pretty fast.

Lawn Rust effects different lawn types at different types.


Now, due to the fact that all lawn types grow at different speeds throughout the year, and rust occurs when the grass is growing slow, the type grass you have will determine when your lawn will get rust.

Warm Season grasses such Zoysia lawns (Zeon or Emerald, Empire, Compadre, Zenith, Jamur)- 

Will most likely get rust during cool, wet springs when the grass is green, but not really growing too fast yet. Or in the fall, when, again, its cooler and you have extended periods of dew or wet nights. These grasses usually naturally grow fast in the summer, so if you get it in the summer, it could be a lack of nitrogen (see below for remedies).

Cool season grasses such as tall fescue or blue grasses


Most likely get rust in the summer. Since they are cool season grasses, they tend to slow their growth in the summer. Combine this with some cool nights and humid weather,  and a chance for rust has just sprung.

Like your grass, rust won't in the winter (below 40-45 degree soil temps)

How to get rid of it? Treatment.

Powdery Orange Dust from Lawn Rust

1. If you think your grass is growing abnormally slow for the time of year (i.e. fescue growing slow in spring when it should be growing fast, or zoysia growing slow in summer) you may need to fertilize the lawn with nitrogen, to speed up the grow rate back to a healthy level.

2. You can also put fungicides as treatment on the       lawn such as Bayleton or Daconil . These usually get rid of the lawn rust, and other fungi pretty quick. Make sure to read the bag for application instructions.

3. Thatch can also help contribute to rust, because the thatch will hold moisture above the soil, and next to the grass blades. You want moisture at the root system in the soil, not above the ground next to the grass blades. Try to reduce the amount of thatch you lawn has by raking it out or bagging excess clippings.

 *Fungicides don't work if soil temps are below 45 degrees or so)

Shady with a Chance of Rust.




Remember, although those orange spots known as lawn rust is not detrimental to your lawn's health, its best to be safe than sorry.

If you have a lawn rust disease, but it is not something you really want to mess with, we would love to help you out. Give us a call today at 866.228.5324 or click this link- Lawn Care.