Preventing Spring Dead Spot in Winter: Essential Steps for a Healthy Lawn
Spring dead spot (SDS) is a frustrating fungal disease affecting warm-season grasses, particularly Bermudagrass, Zoysia, and other turf varieties. While the spots become visible in spring, the infection actually takes root in the cooler fall and winter months. To prevent SDS, lawn care enthusiasts must take proactive winter measures that halt fungal growth and strengthen turf resilience.
In this guide, we’ll explore proven methods for preventing spring dead spot during winter, including how and when to use Headway G fungicide and other essential steps to protect your lawn.
Spring Dead Spot: The Basics
Spring dead spot manifests as unsightly, circular patches in the lawn, often a few inches to several feet in diameter. These patches appear as the grass emerges from dormancy in spring, revealing areas where the fungus has weakened or killed the turf’s root system.
What Causes Spring Dead Spot?
Spring dead spot is caused by fungi in the Ophiosphaerella genus, which thrive during cool, wet periods in fall and winter. The fungus invades turf roots, creating patches of weakened grass that struggle to recover when growth resumes in spring.
Fungicide Application: The Power of Headway G & Pillar SC
Why Use Headway G Fungicide?
Headway G is a specialized granular fungicide combining two potent active ingredients: azoxystrobin and propiconazole. Azoxystrobin acts as a systemic fungicide that gets absorbed into the plant, while propiconazole has both preventative and curative properties. Together, these ingredients create a powerful tool for combating fungi associated with spring dead spot and other common winter turf diseases. The dual-action formulation targets fungal pathogens at different stages of development, making it a versatile choice for both prevention and control and one of the best fungicides for spring dead spot.
Spring dead spot is particularly challenging because it establishes itself in fall and winter, affecting turf roots before visible damage appears in spring. Using Headway G as a preventative measure can significantly reduce the severity of SDS and keep your lawn healthy year-round.
How and When to Apply Headway G Fungicide
1. Timing is critical: Timing your fungicide application is crucial for effective SDS prevention. The best time to apply Headway G is in early to mid-fall, generally from late September to early October, or whenever soil temperatures are still above 55°F but beginning to cool down. This is when the fungus becomes most active at the root level, making it the ideal time for fungicide treatment to prevent infection.
2. Application rates and method:
- For general spring dead spot prevention, use Headway G at a rate of 2 to 4 lbs per 1,000 square feet, depending on the severity of disease pressure and the age and susceptibility of your turf.
- If your lawn has experienced SDS in the past, consider applying the higher end of this range to ensure full coverage and protection.
- Use a broadcast spreader for even coverage, walking in a grid pattern across the entire lawn. Overlapping slightly as you move in rows can help prevent any gaps that might leave your lawn vulnerable.
- Lightly water in the Headway G granules immediately after application. This helps activate the fungicide, allowing it to reach the soil and begin penetrating the root zone.
- Be cautious not to overwater, as excessive moisture can dilute the fungicide's concentration and potentially lead to runoff.
- For best results, consider a second application of Headway G about 30 days after the initial treatment, typically around mid-to-late October or early November. This reinforces the fungicide’s protective barrier and enhances its effectiveness.
- Repeat applications are particularly beneficial for lawns that have experienced SDS in the past or for high-traffic areas that are more prone to disease pressure.
- Using a soil thermometer can be incredibly helpful for timing applications. Apply Headway G when soil temperatures are around 65°F and dropping in the fall, as this is when the SDS fungus is preparing to overwinter. Monitoring soil temperature in early spring can also help you detect when the lawn might be vulnerable to new outbreaks, especially if the disease was present the previous year.
Pillar SC Fungicide
Pillar SC fungicide is an effective liquid fungicide designed for broad-spectrum control of various turf diseases, including brown patch, dollar spot, and spring dead spot. By applying this product as part of your fall turf management routine, you can prevent disease spread, protect your lawn's health through winter, and help it emerge strong and green in spring.
Why Use Pillar SC Fungicide?
Pillar SC combines two powerful active ingredients — pyraclostrobin and triticonazole. This combination offers both preventative and curative action, tackling fungal spores before they can establish and spread through the grass to stop active infections. This dual-action approach provides extended protection, ideal for preventing SDS, which thrives in cooler temperatures when turf is most vulnerable.
Application Tips for Effective SDS Control
1. When to apply:
- Timing: Apply Pillar SC in late summer or early fall, ideally before the lawn goes dormant. This timing allows the fungicide to reach the root zone and disrupt the SDS fungal cycle before winter sets in.
2. Proper application:
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Application rate: Apply at the rate of 1 oz. per 1000 square feet. The rate is the same for preventative and corrective disease control. Target high-risk areas like shaded or compacted spots, which may be more prone to SDS.
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Apply using a battery-powered 4-gallon sprayer with a large droplet nozzle is recommended.
3. Watering in the fungicide:
- Apply 1/4" of water from irrigation or rainfall to move Pillar SC into the soil.
Using Pillar SC fungicide as part of your SDS prevention plan can enhance your lawn’s resilience through winter, helping to ensure a vibrant, disease-free spring.
Complementing Fungicide with Lawn Care Practices
While Headway G fungicide is an effective tool, its performance can be enhanced by pairing it with other lawn care practices, such as aeration, soil pH adjustments, and proper fertilization, as covered in the subsequent sections. A healthy soil environment reduces the need for frequent fungicide applications and promotes stronger turf that can resist pathogens on its own.
Related: The Most Effective Fungicides to Use on Your Lawn
Focus on Soil Health
Healthy soil is the foundation of a resilient lawn. Turf grass thrives in well-balanced soil with adequate nutrients, proper structure, and a favorable pH level. Healthy soil supports robust root growth and discourages the development of fungi, including those responsible for spring dead spot (SDS). Improving soil health as part of your SDS prevention plan involves aeration, pH adjustments, and organic amendments that make the soil environment less conducive to the pathogens causing this disease.
Aerate Your Lawn in Late Summer or Early Fall
Compacted soil restricts the movement of air, water, and nutrients to the root zone, creating a stressful environment for turfgrass. Compaction can weaken roots, leaving them more susceptible to fungal invasion. Aerating your lawn relieves compaction and promotes a healthy root system that can better withstand the stressors associated with spring dead spot.
How and when to aerate:
- Timing: Aerate in late summer or early fall, ideally around August or early September. This timing allows the grass to recover from aeration before the cool fall temperatures arrive, helping the roots to strengthen in preparation for winter.
- Method: Use a core aerator that removes small plugs of soil from the lawn. Core aeration creates channels for air, water, and nutrients to reach the roots, which can reduce compaction and improve overall soil structure.
- Aftercare: After aerating, consider overseeding or applying a light layer of compost to help build up organic matter in the soil. The compost will gradually improve soil structure, boost microbial activity, and support the grass’s nutrient needs.
Related: How to Core Aerate Your Lawn
Adjust Soil pH for Optimal Disease Resistance
Spring dead spot fungi tend to thrive in soil with a slightly alkaline pH (above 6.5). Bermudagrass and other warm-season grasses generally prefer a slightly acidic pH between 5.8 and 6.2. By maintaining a slightly acidic soil environment, you can make conditions less favorable for the pathogens responsible for SDS.
Testing and adjusting pH:
- Soil testing: Start by testing your soil's pH in late summer or early fall to determine if adjustments are needed. You can purchase a soil test kit or have it professionally tested for a more detailed report on nutrient levels and pH.
- Lowering pH: If your soil test shows a pH above 6.5, consider applying sulfur or MAG-I-CAL® PLUS Soil Food for Lawns to bring it down to the desired range.
- Avoid drastic changes: Lowering soil pH too quickly or excessively can stress your lawn, so it’s best to make gradual adjustments over time.
Incorporate Organic Matter to Boost Soil Health
Adding organic matter, such as Essential-G™ Granular Soil Compost & Biochar to your soil improves its structure, nutrient-holding capacity, and microbial activity, creating a healthier environment for turfgrass and making it harder for pathogenic fungi to thrive.
Benefits of organic matter:
- Improves soil structure: Organic matter can improve soil porosity, especially in clay-heavy or compacted soils. Better porosity means more room for air and water to move freely through the soil, enhancing root growth and resilience.
- Increases microbial activity: Healthy soils are rich in beneficial microbes that can help break down organic matter and release nutrients for the grass. These beneficial microbes compete with pathogenic fungi, making it more difficult for harmful pathogens like those causing SDS to establish themselves.
How to apply organic matter:
- Topdressing with compost: After aerating, spread a thin layer of compost (about 1/4 inch) over the lawn. Use the back of a rake to spread the compost evenly and work it into the soil. Topdressing helps improve soil health and provides nutrients that will strengthen the turf.
- Compost tea or humic acid: Another option is to apply liquid compost tea or humic acid. These soil conditioners stimulate microbial activity and improve soil health without altering its structure. Apply compost tea or humic acid every 4-6 weeks during the growing season for best results.
Promote Beneficial Soil Microorganisms
Soil biology plays a crucial role in disease prevention. Beneficial organisms, such as bacteria, fungi, and nematodes, help regulate nutrient cycling, improve soil structure, and suppress disease-causing pathogens. Encouraging a thriving community of beneficial microorganisms in your soil can create a natural defense against SDS.
Ways to encourage beneficial microbes:
- Use organic fertilizers: Organic fertilizers provide slow-release nutrients that feed beneficial microorganisms, unlike synthetic fertilizers that may disrupt microbial activity. Choose fertilizers high in organic matter or nutrients like fish emulsion, blood meal, or bone meal.
- Avoid overusing pesticides: Frequent pesticide use can harm beneficial microbes. Only use pesticides when necessary and avoid treating the entire lawn unless an infestation demands it. Spot treatments are often effective without disrupting beneficial microbial populations.
Adjusting Your Fertilization Practices
Proper fertilization is essential for maintaining a healthy, resilient lawn, but when it comes to preventing spring dead spot (SDS), timing and nutrient balance are key. The fungi responsible for SDS thrive in high-nitrogen environments, especially in late summer and fall when the turf is preparing for dormancy. Adjusting your fertilization practices to provide balanced nutrients at the right times can strengthen your grass, minimize disease risk, and prevent the conditions that promote fungal growth.
Use Balanced Fertilizers in Spring and Early Summer
Spring and early summer are the best times to apply nitrogen-rich fertilizers to encourage healthy growth during the active growing season. Fertilizing during this time helps the grass build strength, develop a deep root system, and become more resistant to stressors, including fungal diseases. When fertilized appropriately in spring, the turf will have the nutrients it needs to establish strong growth, reducing its susceptibility to SDS.
Choosing the right fertilizer:
- Look for a balanced fertilizer: A balanced fertilizer, such as a 14-7-14 (nitrogen-phosphorus-potassium) blend like Complete 14-7-14 - Lebanon Country Club Fertilizer, provides essential nutrients without overloading on nitrogen. Balanced fertilizers encourage root growth, cell structure strength, and overall plant health.
- Consider slow-release options: Using a slow-release nitrogen fertilizer in spring provides a steady supply of nutrients over time. Slow-release fertilizers prevent nutrient spikes that can overstimulate grass growth, helping to avoid stress and reducing the likelihood of fungal diseases.
- Micronutrients for soil health: Choose fertilizers that include micronutrients, such as iron, magnesium, and sulfur, which support overall soil and plant health. Micronutrients can improve turf resilience without adding excess nitrogen.
Reduce Nitrogen Applications in Late Summer and Fall
Applying nitrogen-heavy fertilizers in late summer or early fall can stimulate excessive top growth at a time when your grass should be transitioning into a period of dormancy. The SDS fungi take advantage of nitrogen-stimulated growth, which weakens the root system and increases the grass's vulnerability to infection as it enters the cooler months.
Tips for late summer and fall fertilization:
- Switch to low-nitrogen or nitrogen-free fertilizers: In late summer or early fall, use a fertilizer with lower nitrogen content, such as a 0-0-7 or 12-0-24 blend, which supplies essential potassium without encouraging excessive leaf growth. A great product to see your lawn through the winter is Stress 12-0-24 - Lebanon Country Club Fertilizer.
- Emphasize potassium for root Strength: Potassium is crucial for root development and stress tolerance. By using a potassium-rich fertilizer in late summer, you strengthen the grass’s roots and improve cold hardiness, helping the lawn withstand winter conditions better.
- Avoid quick-release nitrogen: Quick-release fertilizers can cause rapid growth, especially in warm-season grasses, which is detrimental as the lawn prepares to go dormant. Opt for fertilizers with a slow-release or low nitrogen profile if nitrogen is necessary.
Use Biostimulants to Enhance Fertilizer Effectiveness
Biostimulants are organic compounds that support plant growth, nutrient uptake, and resilience. They are especially beneficial in SDS prevention as they improve root health, boost stress tolerance, and enhance the grass’s ability to resist disease.
Common biostimulants for turf health:
- Humic and fulvic acids: These acids improve nutrient uptake and enhance root development, helping grass withstand stresses like drought, compaction, and disease.
- Seaweed extracts: Seaweed provides natural growth hormones and micronutrients that improve stress tolerance and encourage root growth. Seaweed extracts can be applied throughout the growing season, including in fall, to build resilience.
- Amino acids and protein hydrolysates: These biostimulants support plant metabolism and improve the grass’s ability to use available nutrients. They can also enhance root growth, giving the grass a stronger foundation against SDS.
The Golf Course Lawn Carbon Kit — Liquid Soil Amendments is an excellent way to give your lawn all the extra nutrients it needs to prevent lawn diseases over winter and spring.
Application of biostimulants:
- Apply biostimulants alongside regular fertilizer applications in spring and early summer, and continue with monthly applications through fall to build up your lawn's natural resilience.
- Biostimulants are generally safe and can be applied without concern for over-fertilization, making them a low-risk addition to your SDS prevention plan.
Related: The Best Types of Organic Fertilizers for Your Lawn
Mowing Adjustments Before Dormancy
Adjusting your mowing height before dormancy can also reduce the risk of SDS.
- Gradually raise the mowing height in fall: Raising your mowing height in late fall provides more surface area for photosynthesis, allowing roots to store additional energy for winter.
- Avoid scalping: Scalping (cutting the grass too short) weakens turf roots, which makes it easier for SDS fungi to invade. Keep your mowing height moderate as dormancy approaches.
Maintain Proper Irrigation Practices
Watering your lawn correctly during fall and winter can help control soil moisture levels and deter SDS fungi.
- Water moderately: Avoid over-irrigating in fall, as excessive moisture encourages fungal growth. Water only when needed, and focus on providing deep, infrequent watering.
- Improve drainage: Poor drainage can lead to waterlogging, which is ideal for SDS fungi. Consider amending soil with sand or organic matter to improve drainage, especially in high-risk areas.
Plan for Winter Lawn Cover
Winter cover options like light mulching or using frost blankets may help prevent turf damage from freeze-thaw cycles, which can contribute to SDS.
- Light mulching: In colder areas, a thin layer of mulch can protect the roots from extreme temperature fluctuations. However, avoid excessive coverage that could lead to moisture buildup.
- Frost blankets in severe winters: For areas with extreme winter conditions, frost blankets can help protect your lawn. Lay them down only when frost or a severe freeze is expected, as prolonged covering can restrict airflow.
Regular Monitoring and Early Treatment
Once you've implemented preventative measures, monitoring your lawn for early signs of fungal activity will be essential. Although symptoms may not fully manifest until spring, any sign of irregular discoloration or thinning areas in winter could indicate a potential outbreak.
Related: When to Start Mowing Your Lawn in Spring
Building a Resilient Lawn Against Spring Dead Spot
Spring dead spot treatment is a multi-faceted approach requiring early action and continuous care. You can effectively shield your lawn from this stubborn disease by combining strategic fungicide use with sound cultural practices — like proper fertilization, mowing, soil health management, and appropriate winter protection.
Winterizing your lawn with a preventative fungicide like Headway G, alongside these proactive steps, will allow you to tackle SDS before it starts and ensure your lawn returns strong, green, and disease-free when spring arrives.
Golf Course Lawn can help you prevent and eliminate invasive lawn fungi. Browse our range of highly effective insecticides and fungicides to get a healthy, vibrant lawn.