Beautiful, bright green lawns are the envy of every neighborhood. Whether you’re looking to compete in the local best-kept lawns competition, or just like the look of a jewel-bright well-tended lawn, it’s worth putting in a little effort to tend your grass.
When you first spot a few patches of yellow-orange grass, it can be easy to panic. Worse, you might assume that the problem is low-water conditions and quickly over-water your grass in an attempt to fix the problem.
Rust is a fungus, so the best way to get rid of it is to improve the health of your grass and soil, and to avoid creating conditions where the fungus thrives. Common solutions include fertilizing your lawn, mowing more often, and changing how and when you water your lawn.
What Is Lawn Rust?
Before we get into the details of how to treat and prevent lawn rust, you need to know what it is that you’re dealing with.
Rust is a type of grass fungus. The yellow or orange coloring on your grass is the fungal spores and a sign that the fungus is doing rather well in your lawn. Rust is invisible until it’s relatively well established and ready to start spreading spores across your lawn.
You may also see small pustules on your grass. Those are also Rust, and will eventually burst and spread mature fungal spores across your lawn. These can appear before or after you start seeing yellow leaves, but regardless of when you see them, your rust is sure to spread if they are allowed to mature.
All types of turfgrass as vulnerable to rust, but some types are more prone to it than others, including:
- Some varieties of Kentucky Bluegrass
- Perennial Ryegrass
- Zoysiagrass
- Tall Fescue
If you have any of these cultivars in your lawn, you’ll need to be especially careful to avoid rust.
Why Does Grass Get Rust?
Like all fungal infections, rust is an opportunistic organism. It thrives when conditions are favorable, but it doesn’t do well when conditions are less friendly.
Rust is also significantly more likely when your grass is unhealthy. That’s because unhealthy grass is already vulnerable to pests and infections. That means that rust doesn’t have to fight as hard to establish itself and spread.
Over-watering can also create ideal conditions for rust to grow, particularly if there is a lot of moisture right at the surface of the soil and near the grass.
Ideally, rust looks for lower light conditions and little airflow.
Overgrown, overwatered lawns are prime real estate for rust, but even relatively well-maintained lawns can suffer from rust if the soil quality is poor, the lawn is overwatered, or it’s been too long since your last aeration.
As rust advances, you may even start to see bare spots in your lawn where the rust has killed off all the grass.
How to Deal With Rust:
Once you notice rust in your yard, acting fast can save you some of the more costly solutions like replacing your turf. The key is figuring out the cause of your rust, and working to create better conditions for your grass, and worse conditions for your rust.
Fertilize and Address Soil Problems
One of the first things you can do is make sure your lawn has adequate food, and that the soil conditions are favorable for your grass. If it’s been a while since you last fertilized, go ahead and lay down some basic fertilizer to start.
If you know that your soil has PH problems, low organic content, or other issues (no shame here. Perfect soil is very rare, and hard to maintain) you may want to address those now. Contact your local nursery or home improvement garden center for advice if you aren’t sure how to address any known issues.
Often, there are good combination products available that will help with several issues at once. Many also lay down fresh seed to help replace the unhealthy grass you have now.
Of course, you may not know what condition your soil is in in the first place.
While there are home test kits, a better option is to see if your state or any of the local universities offer soil testing services. Send off a small sample of your soil, taken from different areas of your lawn, and you’ll get a more complete test, and may receive some recommendations for ameliorating the soil.
Try Watering Less
There’s no one hard and fast rule for watering your lawn. Different grass cultivars may need different treatment, depending on your climate and soil conditions. If you’re constantly wondering how your neighbor has such low-maintenance grass, chances are they have a different type of grass than your lawn.
Rust thrives in moist conditions, so by reducing how often you water, you’ll make the conditions less favorable.
Make sure you still water long enough to saturate the soil down several inches. Surface water is a problem, but healthy grass should have deep roots, and longer, less frequent watering can help your grass develop those deep roots.
Pro-Tip: If you have automatic sprinklers when you notice rust in your lawn, you should turn them off and switch to manual watering right away. Over-watering is one of the biggest causes of rust. By manually watering only when your lawn really needs the moisture instead of on a schedule, you’ll improve grass health and take away one of the most important environmental conditions for rust.
Mow and Remove Clippings
Mowing may seem a little counterintuitive since the rust wants to spread spores across your lawn, but it’s an incredibly important step.
Mowing your lawn helps thin your grass. That means more sun penetration and more airflow. Both are bad news for rust fungi. Mowing your lawn also makes room for fresh grass to grow in where the old grass was. It also works to remove unhealthy and infected grass before the rust spores have time to mature and spread.
Just make sure you’re removing all the clippings, otherwise, the clippings will likely hold moisture and prevent airflow, making your rust woes worse.
Try A Fungicide
As a last-ditch effort to get rid of rust, you may want to consider a chemical fungicide. These treatments are effective, but they can be hard on your lawn and your other plants. It’s better to solve rust problems without a fungicide, but if your rust has gotten out of control, it may be the best option.
Only treat areas of your lawn with active rust. Preventively treating the rest of your lawn may cause more problems than it solves.
Frequently Asked Questions:
What Causes Rust in My Lawn?
There are tons of possible causes of rust. Most types of grass are at least a little vulnerable to rust, and the spores are everywhere. Rust takes an opportunity to develop when conditions are right, like too much moisture and not enough light. It’s also a lot more likely if your grass is already stressed or unhealthy.
Is Rust Harmful to People or Pets?
The good news is that, while rust can damage your lawn, it isn’t likely to cause problems for you or your pets. The spores will get on your shoes, and maybe even your clothing, but it’s not toxic to humans.
Dogs may also get colored with rust spores, but it’s not harmful to them. Just give your pooch a quick wipe down with a damp cloth to prevent the yellow color from the spores getting everywhere inside.
