Summer Patch: The Root-Killing Fungus That Hits When You Least Expect It
- Danny at Spring Touch
- Jun 24
- 2 min read
Think your lawn just can’t handle the heat? If big yellow or bronze patches start showing up mid-summer, you might be dealing with Summer Patch—a lawn fungus that hits hard and damages deep.
It may not sound like a big deal, but this fungus doesn’t just mess with your grass blades—it attacks the roots, making it one of the more destructive summer lawn diseases we see in Minnesota.
What Does Summer Patch Look Like?
It usually starts subtly:
Small, circular patches of thin, wilted grass
Over time, those patches grow and merge into larger, irregular areas
Colors range from yellow to bronze, and the dead turf can span 6 inches to 3 feet wide
From a distance, it may look like heat damage—but the issue runs deeper.
Want to compare what you’re seeing? Here's a helpful resource from the Michigan State University:
Why It Happens
Summer Patch loves:
Compacted soil and poor drainage
Hot, wet weather—especially in late spring and summer
Lawns that are mowed too short
Turfgrass like Kentucky Bluegrass and Fine Fescues
It thrives in stress-prone areas and takes hold when the roots can’t get the oxygen or nutrients they need.
How to Tell If It’s Really Summer Patch
Still not sure? Try pulling up a section of grass from the affected area.
If the roots are short, black or dark brown, and look rotted—it’s likely Summer Patch. Healthy roots, by contrast, are longer and pale in color.
What You Can Do About It
Step 1: Aerate annually
Liquid aeration helps relieve soil compaction and improves drainage—two major factors in Summer Patch outbreaks.
Step 2: Mow smart
Keep your grass height between 2.5 and 3 inches. Mowing too short adds stress and makes your lawn more vulnerable.
Step 3: Water deeply and early
Avoid frequent shallow watering. Instead, water early in the morning so the lawn dries out before evening.
Step 4: Fertilize with care
A consistent fertilizing schedule strengthens your lawn’s roots and builds resistance to disease. Don’t overload with nitrogen, though—especially in summer.
Step 5: Still not sure? Send us a photo
If you’re unsure whether it’s Summer Patch or something else, just text (507) 934-5296 or email us a photo at info@springtouchlawn.com. We’ll take a look and help you diagnose the issue.
Recurring Summer Patch? We’ve Got You Covered
This is one of those lawn diseases that tends to come back in the same spots year after year. If you’ve been dealing with it more than once, it’s time to call in the pros.
At Spring Touch, we offer fungus control treatments specifically formulated to target Summer Patch and other root-damaging fungi. We also focus on improving your lawn’s overall health to prevent future outbreaks.
