How to Prevent Lawn Disease in the Fall

We have officially entered the fall season and temperatures are dropping. It is about the time of year for homeowners to begin noticing irregular patches of brown grass throughout their lawns. It is important to know that while temperatures drop outside, soil conditions also change. This results in a few changes in your grass and creates optimum environments for disease to take over. Read on to learn more about how you can prevent fungus in your lawn this season.

How do I prevent lawn disease during the fall?

There are a few actionable recommendations for preventing lawn disease. Generally, disease loves shady, moist areas in your lawn. Reducing this kind of environment will help significantly.

Reduce Watering

You can start by reducing the amount of moisture in your lawn by changing your watering habits if you are watering too frequently. You will still want to water your lawn to prevent stress—just reduce the amount of time spent doing this. Watering in the mornings is recommended so that the sunlight helps your lawn dry before cooler temperatures occur during nightfall. Water your lawn less frequently and water deeper during the times you schedule for irrigation.

Manage Fallen Leaves

Remove fallen leaves during this time of year as well. Leaves create shady areas in your lawn that encourage disease due to the lack of sunlight. Click here to read more about how to manage them.

Loosen Compact Soil

Make sure your soil is absorbing the water appropriately. If you have really compact soil where water tends to pool up, consider aerating or raking in a mix of topsoil to help. For more information on compact soils, read Soil Management for Lawns and Gardens.

Apply Fungicide Preventatively

One of the best recommendations for preventing lawn disease is to make preventive applications of a systemic fungicide. This helps to prevent lawn disease from occurring in the first place.

How do I apply fungicide preventatively?

It is recommended you apply a fungicide at preventative rates around this time as it will help the grass enter colder months in a healthier condition. If you have had a fungus before, you may need multiple applications in affected areas from the past. If spring dead spot was a problem, apply a fungicide at high rates to the problem area(s). Consider mapping those areas because fungicide treatment can be expensive. The use of a spray dye like the one linked below may help you. If you use a granular fungicide variety, water the lawn immediately after application to help with soil absorption.

What is the difference between preventive and curative application rates?

Fungicides can be applied at two rates: preventively or curatively. Preventive rates are less than curative rates. Preventive application rates should be used to prevent lawn disease whereas curative application rates should be used to “cure” an already present disease.

As mentioned in our blog on Lawn Disease Control Strategies, we believe an ounce of prevention is worth a pound of cure. In other words, preventive application rates are significantly less than curative application rates for lawn disease. Since you will apply more fungicide at a curative application rate, you will also spend more money. If you play it safe and apply fungicide at preventive rates, the likelihood of experiencing lawn disease in the first place is less—plus, you apply at smaller application rates and therefore save more money. Your grass will not endure stress or damage as well.

 It is always good to go ahead and apply fungicide preventively so you don’t wind up spending more money.

What are some common lawn diseases in the fall?

As with any lawn disease, the type of fungus you may be experiencing really depends on your climate and location. However, some of the most common lawn diseases we see in the fall are brown patch, large patch and dollar spot. See the images below for visual representations of what these diseases look like in lawns. Be sure to also check out our Identifying Common Lawn Diseases article for more information.

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Pictured above from left to right: Brown patch, large patch and dollar spot.

What are some recommended fungicides for this time of year?

Most bags or bottles of fungicide will instruct you on how much you should be applying, but generally speaking, curative rates are four to five times higher than preventive rates.

Lastly, it should be noted that having a healthy lawn that is properly fertilized with the right amount of nutrients will ensure that your grass bounces back from disease or insect pressure pretty quickly. Sod University recommends the Lawnifi fertilizer program for this reason. Lawnifi is powered by Catalyst Technology^TM, which nano-sizes the nutrients to make them plant available. This allows your grass and other plants to easily absorb them with the use of less product. Learn more about Lawnifi at Lawnifi.com or by reading Why Use Lawnifi Fertilizer? If you currently have an existing lawn disease or suspect one in your lawn, avoid fertilizers rich in nitrogen content as this will serve to feed the lawn disease and promote its growth.

If you have a warm season lawn, be sure to check out our Sod University blog, Beware of Late Fall Fungus for Warm Season Lawns. For generalized disease control information that also discusses how to treat present lawn disease, read Lawn Disease Control.