When you control weeds by type you get better results faster, easier, and cheaper. For example, you need good-quality systemic herbicides to kill perennials, but you can deal with annual broadleaves with homemade weed killers and frequent mowing.
In this article, we discuss the main weed control tips to consider when adjusting your weed management strategy for each type of weed that infests your lawn.
Weed control tips for grassy weeds
Grassy weeds look like your turfgrass, though most stand out in lawns by their size, color, and texture. They have round, hollow stems and long, narrow leaves, oriented vertically, that offer little surface for contact herbicides.
When planning to remove grassy weeds from your lawn, keep these tips in mind:
- Hand-pulling and digging are less effective for grassy weeds that spread through stolons and rhizomes, such as creeping bentgrass. If you try these methods, do your best to remove the entire root system.
- Grassy weeds’ physiology is similar to that of your turfgrass. They are best controlled with selective post-emergent weed killers that are safe for your turf type. Fenoxaprop-P-ethyl and quinclorac are two active ingredients Sam Bauer, a teaching specialist at the University of Minnesota, recommends. Aaron Steil at Iowa State University also mentions fluazifop-p, sethoxydim, and clethodim.
- If a stubborn grassy weed takes over the lawn, you might need to use non-selectives like glyphosate (Roundup), glufosinate (Finale), or diquat. The similar appearance makes spot treatments difficult in this case. Typically, you’d treat the entire weedy area and then reseed the turfgrass.
Read more about grassy weeds management methods in our guide, “How to Identify and Control Grassy Weeds.”
Weed control tips for broadleaf weeds
Broadleaf weeds have wider leaves with more surface area for contact herbicides. They’re also easier to identify in turf, making spot treatments more precise and safer for the surrounding grass.
Here’s what to remember when dealing with broadleaf weeds:
- Most broadleaf weeds signal nutrient or pH imbalances in the soil. Start your weed control plan with a soil test and correct the deficits with soil amendments and proper fertilization.
- Many broadleaf species have long tap roots. To prevent regrowth, you’ll need to dig deep and remove the entire root system.
- On seedlings with less than six leaves, try a homemade contact weed killer such as vinegar or baking soda. For good results on larger weeds you’ll need multiple applications.
- Use selective broadleaf herbicides for targeted chemical control. Stephen Hart, extension specialist in Weed Science at Rutgers recommends products with 2,4-D, dicamba, MCPA (2-methyl-4-chlorophenoxyacetic acid), MCPP (methylchlorophenoxypropionic acid), dichlorprop, triclopyr, or sulfentrazone as active ingredients.
- Choose a selective herbicide effective for the type of broadleaf weed in your lawn, or buy a product that combines two or three active ingredients and has a broader coverage.
- Alternatively, you can try spot treatments with non-selective weed killers such as glyphosate if you keep the solution away from your turfgrass.
Learn more about broadleaf weeds and how to manage them from our guides, “How to Identify and Control Broadleaf Weeds.”
Weed control tips for annual weeds
Annual weeds invest most of their energy in growing their above-ground structures and in flowering and spreading seeds. They have smaller, shallower roots and only live for a single year. Once a plant dies, it doesn’t regrow the next season, so your major concern in this case is to limit the seed spreading.
Follow these tips to improve the weed control strategy for annuals:
- Apply a pre-emergent herbicide in early spring to control summer annual weeds (e.g., goosegrass, crabgrass, tumbleweed) or late summer and early fall to control winter annual weeds (e.g., henbit, common chickweed, annual bluegrass).
- Periodically mow the lawn during the flowering and seeding season to prevent seed heads from forming. Bag the grass clippings; don’t use them as mulch or in your compost bin.
- Hand-pull annual weeds if they are present in small numbers. Their short roots make them easy to control through hand weeding. Annual weeds don’t regrow if you succeed in pulling out at least part of the root system.
- Apply a post-emergent herbicide once weeds sprout. Both contact and systemic weed killers work in this case, including homemade weed killers with vinegar, citric acid, essential oils, or boiling water.
Weed control tips for biennial weeds
Biennials live for two seasons. During their first season, biennials only grow leaves, most often in a rosette that keeps close to the soil. Flowering and seeding happen in the second year when they grow a tall flowering stalk.
As with annuals, the best strategy to limit their number is keeping them from flowering and spreading seed. Keep these tips in mind when dealing with biennial weeds:
- Hand-pull scattered plants or use a spade to sever the root below the crown (a couple of inches below the soil level). This prevents them from regrowing.
- Mow the weeds down to prevent second-season biennials from forming seed heads. “Biennials have dormant crown buds that often initiate growth after removal of the primary stalk; thus, a second mowing 3 to 4 weeks after the initial mowing often is required,” says Bob Hartzler, extension weed scientist at Iowa State University, who has decades of experience studying weeds all over the world.
- Apply a post-emergent herbicide in the fall or early spring. Hartzler explains that’s when biennials are in the rosette stage and more susceptible to weed killers. “The number one problem in managing biennials is delaying herbicide application until after the stem has initiated elongation (bolting). Biennials become much more tolerant to herbicides at this stage and frequently escape control,” he adds.
Weed control tips for perennial weeds
Perennial weeds are there to stay. They regrow from their deep root system year after year and live for more than two years. Perennial spread through seeds, but also through vegetative parts such as rhizomes, stolons, bulbs, tubers. The bottom line: They’re hard to remove once established.
Use these tips to improve your weed control strategy:
- Mow the grass regularly. It prevents perennial weeds from forming seed heads and limits their ability to store energy in their below-ground structures, thus making them weaker during winter and limiting their spreading through vegetative parts.
- Hand-pull perennial weeds when young and if in small numbers. This method works if you manage to pull out the entire root system; otherwise, the plant will regrow from the root fragments left in the ground.
- Apply pre-emergent herbicides. This method only helps prevent seeds already in the soil from sprouting. It’s less effective on vegetative buds that grow from stolons or rhizomes of established perennials.
- Apply a post-emergent systemic herbicide. It’s the most successful type of treatment for perennial weeds, because a systemic weed killer can move through the plant and damage it from leaves to roots.
- For best results, spread the systemic herbicide early in the fall — when weeds transport more energy into the roots, prepping for dormancy — and just before or during flower buds. Applications are less effective during foliage growth in early spring when energy stored during winter in their roots is sent above ground to feed the vegetative growth.
You’ll get better results if you identify the perennial weeds in your yard and figure out the best treatment for each type invading your lawn. Here are four guides covering some of the most common perennial weeds with detailed information on how to keep them at bay:
- “How to Treat Dandelions in Your Yard”
- “How to Get Rid of Poison Ivy in Your Yard”
- “How to Get Rid of Clover on Your Lawn”
- “How to Identify and Get Rid of Nutsedge in Your Lawn”
- “How to Get Rid of Creeping Charlie”
General tips and rules
If you’re new to lawn care, here are a few guides to help you get a hang of the weed control process, products and timing:
- “Why Do Weeds Grow?”
- “13 Most Common Lawn Weeds (and How to Get Rid of Them)”
- “When and How to Apply Pre-Emergent Herbicides”
- “How and When to Apply Post-Emergent Herbicides”
FAQ about weed control by type of weed
What is the best form of weed control?
The best form of weed control is prevention. You do this by:
- Keeping the soil covered: mulching, planting groundcovers where turf struggles, overseeding thinned turfgrass, applying a weed fabric
- Treating the lawn with pre-emergent herbicides
- Keeping the lawn care equipment clean
- Buying good quality weed-free grass seeds
What is the hardest weed to control?
Perennial weeds are hardest to control because they have many ways to survive and spread. But even among perennials, there are some that are more challenging than others, such as:
- Violets Viola
- Ground ivy or creeping Charlie
- Wild strawberry
- Mossy stonecrop
- Yarrow
How much does weed control cost?
Weed control services range from $65 – $165 for a ¼ acre lot, but the price varies with the method used, the type of herbicide and the type of weeds they need to remove. Find out more from our guide, “How Much Does Weed Control Cost in 2024?”
It’s time to call the weed control pros!
Many homeowners wait too long and only hire a pro when weeds are taking over the turf. At that point, they often end up reseeding the entire lawn. Early interventions are cheaper and give better results. Don’t wait too long. Find a local weed control expert with Lawn Love and protect your beautiful, lush turfgrass from nasty, persistent weeds!
Sources
Bauer, S. (n.d.). Options for controlling weeds in your lawn this summer. University of Minnesota. https://turf.umn.edu/news/options-controlling-weeds-your-lawn-summer- Hart, S. (2003, July). Broadleaf Weed Control in Cool Season Turfgrasses. Rutgers, the State University of New Jersey. https://njaes.rutgers.edu/fs385/
- Hartzler, B. (2006, April 3). Now’s the time to control biennial weeds. Iowa State University Extension and Outreach.
- https://crops.extension.iastate.edu/encyclopedia/nows-time-control-biennial-weeds
- Steil, A. (2024). How to Manage Perennial Grassy Weeds in the Garden and Lawn. Iowa State University Extension and Outreach. https://yardandgarden.extension.iastate.edu/how-to/how-manage-perennial-grassy-weeds-garden-and-lawn
Main Photo Credit: Amy Stenglein | Lawn Love
