If your Indianapolis lawn went from green in April to weedy in June, crabgrass and nutsedge are most likely the cause. Pre-emergent season is already closed, so you need selective post-emergent products to handle each weed separately. Quinclorac targets crabgrass, while a sedge-specific product with sulfentrazone or halosulfron handles nutsedge. Skip the generic weed and feed in summer heat, or you will stress your grass and the weeds will come right back.
What are the two weeds taking over Indianapolis lawns right now?
Drive through Carmel, Fishers, or Noblesville this week and you will see it on almost every block. Lawns that looked clean and green in April are suddenly speckled with light green patches and tall, pointy blades. Homeowners are calling Fine Touch Services in a panic because their grass looks ragged less than two months after spring green-up.
The culprits are almost always the same two weeds. Crabgrass and nutsedge thrive in central Indiana summers, and they spread fast once daytime temperatures stay in the 80s. The good news is that both are very treatable once you know which one you are looking at and which product to reach for.
How do you tell crabgrass and nutsedge apart in your yard?
Crabgrass is the low-spreading, light green stuff that fans out flat against your lawn. It looks like a starfish of pale blades pressed close to the soil, and it almost always shows up first in thin or sunny spots along driveways, sidewalks, and curbs.
Nutsedge is the opposite. It shoots straight up, looks shinier than the rest of your grass, and grows about twice as fast as your turf. If you mow on Saturday and by Wednesday there are tall, pointy blades sticking up everywhere, that is nutsedge waving at you. One weed hugs the ground, the other reaches for the sky, so once you know the difference you can spot them from the driveway.
Why is pre-emergent season already over for the year?
Here is the hard truth. Pre-emergent is the product you put down in early spring to stop weed seeds from ever sprouting. In central Indiana, that window typically closes around the time soil temperatures climb past the mid 50s, which usually happens in April.
Once you can actually see crabgrass and nutsedge in your yard, the pre-emergent window is shut until next year. Putting more pre-emergent down now will not undo what has already sprouted. From here on, you need post-emergent products that target the living plant, not the seed.
What actually kills crabgrass without nuking your lawn?
For crabgrass, you need a selective post-emergent. The active ingredient to look for on the label is quinclorac. It targets crabgrass and a few other broadleaf weeds while leaving your good Kentucky bluegrass, fescue, and rye alone.
Read the label closely and follow the rate for your grass type. Spot-treat the patches you can see instead of broadcasting it across the entire yard. Try to apply on a calm morning when temperatures are below the mid 80s, and water it in only if the label tells you to. That keeps your healthy turf strong while the crabgrass dies off.
What is the right treatment for nutsedge in Indiana?
Nutsedge is a totally different plant, and quinclorac will not touch it. For nutsedge, you need a sedge-specific product. Look for an active ingredient like sulfentrazone or halosulfron on the bottle. Both are designed for sedges and will leave your turf grass standing.
Plan on more than one application. Nutsedge grows from underground tubers called nutlets, and a single spray rarely takes care of them all. Treat once, wait the interval listed on the label, then come back and hit any new shoots. Two well-timed applications usually clean up a yard for the rest of the season.
Why should you avoid generic weed and feed in summer?
Whatever you do, do not blast your whole yard with a generic weed and feed product in the middle of a central Indiana summer. Those bagged products are designed for cooler weather and broad weed control, and they tend to stress cool-season grass when temperatures push into the high 80s.
You end up with thinner, weaker turf right when crabgrass and nutsedge are looking for any open spot to take over. Within a few weeks, the weeds come right back into the gaps, and the cycle starts again. Two weeds, two different treatments, and timing matters more than horsepower.
If you would rather skip the trip to the store and the guesswork, Fine Touch Services can handle it for you. Our team treats lawns across Carmel, Fishers, Noblesville, Westfield, and the rest of the Indianapolis area every week, and we know which product to use, when to use it, and how to keep your turf healthy through the rest of the summer. Get a free quote at finetouchservices.com or learn more about our lawn care services.
"Crabgrass hugs the ground and nutsedge shoots straight up. Two completely different weeds, two completely different products. Use quinclorac on the crabgrass, a sedge-specific product on the nutsedge, and keep the generic weed and feed out of your yard in July."
— Jake Morris, Owner of Fine Touch Services
Frequently Asked Questions
Can I still put down pre-emergent in June or July in Indianapolis?
No. Pre-emergent works by stopping weed seeds from sprouting, and that window closes once soil temperatures climb past the mid 50s in April. By June or July in central Indiana, crabgrass and nutsedge have already germinated, so a post-emergent product is the right move for the rest of the season.
What is the easiest way to tell crabgrass from nutsedge?
Crabgrass spreads low and flat like a pale green starfish pressed against the soil, usually along driveways and curbs. Nutsedge stands straight up, has a shiny, almost waxy look, and grows noticeably faster than your turf grass. If you see tall, pointy blades sticking up a few days after mowing, that is nutsedge.
Will quinclorac kill nutsedge too?
No. Quinclorac is great on crabgrass and some broadleaf weeds, but it does not control nutsedge. For nutsedge you need a sedge-specific product with sulfentrazone or halosulfron as the active ingredient. They are different plants and need different chemistry.
Why is generic weed and feed a bad idea in the summer?
Weed and feed products are formulated for cooler weather and broad weed control. Applying them when central Indiana temperatures climb into the high 80s tends to stress cool-season grasses like Kentucky bluegrass and fescue. The turf thins out, the weeds come right back into the gaps, and you end up worse off than when you started.
How many treatments does nutsedge usually need?
Plan on at least two applications. Nutsedge grows from underground tubers called nutlets, and a single spray rarely takes care of all of them. Treat once, wait the interval on the product label, then come back and spot-treat any new shoots. Two well-timed applications usually clean up a yard for the season.
Does Fine Touch Services treat crabgrass and nutsedge for homeowners in Carmel and Fishers?
Yes. Fine Touch Services treats lawns across Carmel, Fishers, Noblesville, Westfield, Zionsville, and the greater Indianapolis area every week. We identify the weed, choose the right selective product, and time the application so your turf stays healthy through the rest of the summer. You can get a free quote at finetouchservices.com or call (317) 771-2332.
Jake Morris
About the Author
Jake Morris is the founder and owner of Fine Touch Services, a top-rated lawn care and landscaping company proudly serving Indianapolis and its northern suburbs since 2018. With a passion for outdoor living and a commitment to customer satisfaction, Jake leads a skilled team that delivers high-quality lawn, landscape, and hardscape services to over 8,000 clients annually. From designing serene garden retreats to building backyard entertainment spaces, Jake brings dedication, expertise, and a personal touch to every project. Learn more about Fine Touch Services. Or connect with Jake on LinkedIn.
