One day your lawn looks healthy. A few days later, mysterious brown or yellow patches appear and start spreading. If you’ve experienced this frustrating scenario, you’ve likely dealt with lawn disease—and you’re not alone. Charlotte’s warm, humid climate creates ideal conditions for fungal diseases that can damage or destroy turf grass.
The good news: most lawn diseases are preventable with proper care, and treatable when they do occur. This guide covers the most common lawn diseases in the Charlotte area, how to identify them, and what you can do to protect your turf.
Why Charlotte Lawns Are Prone to Disease
Our Piedmont climate combines several factors that promote fungal growth:
- High humidity – Especially during summer months, moisture in the air stays elevated
- Warm temperatures – Most lawn fungi thrive between 70-90°F
- Heavy clay soil – Retains moisture and can stay wet too long
- Summer storms – Frequent afternoon thunderstorms keep grass wet
- Warm nights – Extended warm, humid nights let fungi spread rapidly
These conditions explain why disease pressure peaks in Charlotte during late spring and summer—exactly when you want your lawn to look its best.
Lawn diseases are caused by fungi, not insects or nutrient deficiencies. While the symptoms may look similar, treatment is completely different. Proper identification is essential before taking action.
Common Lawn Diseases in Charlotte
Brown Patch (Rhizoctonia solani)
Most common in: Tall fescue lawns during summer
Appearance: Circular patches ranging from a few inches to several feet in diameter. Patches are tan or brown with a darker “smoke ring” border visible in early morning. Individual grass blades show tan lesions with dark brown borders.
Conditions that trigger it:
- Night temperatures above 65°F combined with daytime temps above 80°F
- Extended periods of leaf wetness (6+ hours)
- High nitrogen fertility, especially from quick-release fertilizers
- Poor air circulation and excessive shade
Impact: Brown patch damages leaves but usually doesn’t kill the crown or roots. Affected areas typically recover once conditions improve, though the lawn may look thin until fall overseeding.
Brown patch is so common in Charlotte fescue lawns that it should be expected every summer. The question isn’t whether it will appear, but how severe it will be and how quickly you can limit the damage.
Dollar Spot (Clarireedia jacksonii)
Most common in: Bermuda, zoysia, and fescue lawns, especially when underfertilized
Appearance: Small, silver-dollar-sized spots (2-6 inches) that may merge into larger irregular areas. Grass blades show tan lesions with reddish-brown borders. In early morning, white cobweb-like mycelium may be visible on affected grass.
Conditions that trigger it:
- Low nitrogen fertility
- Drought stress combined with heavy dew
- Temperatures between 60-85°F
- Compacted soil and poor drainage
Impact: Dollar spot can kill grass to the crown if severe, creating permanent bare spots that require reseeding.
Pythium Blight (Pythium species)
Most common in: Cool-season grasses during hot, humid weather
Appearance: Irregular patches that appear water-soaked or greasy. Grass may collapse and mat together. In early morning, cottony white mycelium may be visible. Spreads rapidly along drainage patterns or mower paths.
Conditions that trigger it:
- Daytime temps above 85°F with humid nights above 68°F
- Poor drainage and standing water
- Excessive nitrogen
- Soil calcium deficiency
Impact: Pythium is highly destructive and can kill grass quickly. It spreads rapidly, especially when carried on mower wheels or foot traffic through wet turf.
Spring Dead Spot (Ophiosphaerella species)
Most common in: Bermuda grass lawns
Appearance: Circular dead patches (6 inches to 3 feet) that appear as bermuda breaks dormancy in spring. Patches remain dead while surrounding grass greens up. Affected areas may have a sunken appearance.
Conditions that trigger it:
- Infection occurs in fall when soil is between 60-70°F
- Symptoms appear the following spring
- High nitrogen fertilization in late fall
- Thatch buildup exceeding ½ inch
Impact: Spring dead spot kills bermuda grass to the roots. Affected areas must fill in from surrounding grass or be reseeded/resodded.
Gray Leaf Spot (Pyricularia grisea)
Most common in: St. Augustine grass (rare in Charlotte) and perennial ryegrass
Appearance: Oval or diamond-shaped lesions on grass blades, gray with dark brown borders. Severely affected areas appear scorched or burned.
Conditions that trigger it:
- Hot, humid weather (85°F+ with high humidity)
- Excessive nitrogen, especially from quick-release sources
- Compacted or stressed turf
Take photos of disease symptoms when you first notice them, including close-ups of affected grass blades. Morning photos when dew is present often show diagnostic features like mycelium that disappear later in the day.
Disease Prevention Strategies
The most effective disease management is prevention. These cultural practices significantly reduce disease pressure:
Watering Practices
- Water early morning (before 8 AM) so grass dries before evening
- Water deeply but infrequently – 1 inch per week in 1-2 applications
- Avoid evening watering that keeps grass wet overnight
- Reduce irrigation during humid periods when natural moisture is high
Mowing Practices
- Mow at proper height – Fescue at 3-4 inches, Bermuda at 1-2 inches
- Never remove more than ⅓ of blade in a single mowing
- Keep blades sharp – Dull blades tear grass, creating disease entry points
- Mow when grass is dry to avoid spreading fungal spores
- Clean mower deck between mowing diseased and healthy areas
Fertilization Practices
- Use slow-release nitrogen sources – Quick-release nitrogen promotes lush growth susceptible to disease
- Avoid heavy nitrogen in summer for fescue lawns
- Maintain adequate potassium – K strengthens cell walls and disease resistance
- Follow soil test recommendations rather than guessing at rates
Cultural Practices
- Improve air circulation – Prune low tree branches and dense shrubs near lawn
- Address drainage issues – Standing water promotes multiple diseases
- Core aerate annually – Reduces compaction and thatch
- Overseed fescue annually – Maintains density with newer disease-resistant varieties
When to Treat for Disease
Fungicide applications are most effective as preventive treatments before disease appears, or at the very first signs of infection. Once disease is well-established, fungicides can only stop further spread—they won’t repair existing damage.
Preventive Treatment
For lawns with recurring disease problems, preventive fungicide applications make sense:
- Brown patch prevention: Apply when night temps consistently exceed 65°F (typically early June in Charlotte)
- Dollar spot prevention: Maintain adequate fertility; fungicides rarely needed if nutrition is proper
- Spring dead spot prevention: Apply in fall (September-October) before soil temps drop below 70°F
Curative Treatment
If disease appears, prompt treatment limits damage:
- Apply fungicide at first signs of infection
- Follow label rates and reapplication intervals
- Most fungicides require 2-3 applications at 14-21 day intervals
- Adjust cultural practices simultaneously to address root causes
Over-the-counter fungicides from hardware stores are generally less effective than professional-grade products. They may suppress symptoms temporarily without actually controlling the disease, leading to recurring problems.
Recovery After Disease Damage
Once the disease is controlled and conditions improve, help your lawn recover:
For Fescue Lawns (Cool-Season)
- Wait for cooler weather – Fescue recovers best in fall
- Aerate in September to prepare for overseeding
- Overseed damaged areas with disease-resistant varieties
- Apply starter fertilizer to support new grass establishment
For Bermuda and Zoysia Lawns (Warm-Season)
- Maintain proper fertility – Healthy grass spreads to fill thin areas
- Keep mowing and watering normally – Supports recovery
- Consider plugging or sprigging large bare areas for faster fill-in
- Be patient – Warm-season grass recovers during summer growing season
Professional Disease Control
Our disease control program provides both preventive and curative treatments timed for Charlotte’s disease pressure cycles. We use professional-grade fungicides at proper rates, combined with recommendations for cultural practices that reduce disease susceptibility.
If you’re seeing recurring disease problems despite your best efforts, or if you’re not sure what’s affecting your lawn, we can diagnose the issue and develop a treatment plan that addresses the specific conditions on your property.
Disease problems often indicate underlying issues with watering, fertility, or soil conditions. Our lawn care program addresses these root causes while providing the nutrition and weed control your lawn needs to resist disease naturally. Get a free quote for comprehensive lawn care.