Common Lawn Weeds & How to Control Them

“A weed is a plant that has mastered every survival skill except learning how to grow in rows!”

- Doug Larson

Weeds! They’re really not the bad guy …. they’re just in the wrong place at the wrong time! They especially enjoy the comfy environment that our manicured lawns provide. However, these rugged, adventitious plants have hard-earned their place after generations of survival in far harsher environments and know a thing or two about how to thrive where they’re not wanted.

While it isn’t so bad to let a few Violets, Creeping Charlie, or Clover run amok in the back corners of your yard, the front lawn is usually best maintained on par with the Joneses. 

Many of these are edible and medicinal plants like Dandelions, Chickweed, Purslane, and Lambsquarters that were intentionally brought here by immigrants because these leafy vegetables grew anywhere and everywhere fast, providing them nutrient-dense greens, while others traveled here in horseshoes and boot treads. Earning many names like White Man's Footprint because they sprung up everywhere colonial travelers went.

The Scourge of White Picket Fences

Before you villainize these plants for just doing what comes naturally, it’s important to understand why they’re growing in your lawn in the first place! 

That enriched environment, regular moisture, and regular applications of fertilizer really do make the grass greener in your manicured lawn, and a verdant paradise when compared to cracks in the sidewalk or growing in the gutter! We’ve cultivated the soil, removed their competition, and given them everything they could hope for!

Typical lawn grass is in the monocot family and that is why broadleaf weed killers destroy everything else that doesn’t grow with parallel veins! Knowing what to apply and when can make or break your pretty green lawn!

While gardeners like myself prefer the organic ‘eat the weeds’ approach, we’d rather dig up Purslane to move it into the vegetable garden, or dig Dandelion roots to roast for caffeine-free coffee substitutes! There are loads of other methods available to you for a clean, green expanse of turf!

Common Lawn Weeds and Their Control

While no two weeds are alike, there are 3 main types:

• The first is your typical native wildflower that is only trying to grow in its ever-shrinking environment. Not all are the prettiest or showiest and fall into the background noise of greenery.
• The second is the noxious weed that, while also a wildflower of sorts, comes with an attitude. These can be somewhat harmful to crops, health, wildlife or property. Some of these weeds are poisonous to livestock and our pets (and us!) or have skin-irritating spurs, burs, and sap. Others invade agriculture and reduce crop health and size, costing loads of money to remove them and causing crop loss.
• The third category is invasive weeds. Non-native imports that are both wildflowers brought over from elsewhere and have now erupted into the landscape like a kid in the candy store. Without the usual checks and balances of insect and animal browsing, or climate controls, they are running rampant today. Kudzu and some forms of English Ivy, Some types of Purple Loosestrife and so many others have been inadvertently given prime growing conditions with no competition, and can easily take over a non-native area … fast. 

It’s the less aggressive, more polite native plants and our lawns that invasives are out-competing or completely outgrowing. That is when they become a problem.

Top Lawn Weeds

“Sedges have edges and Rushes are round

Grasses have knees that bend to the ground.”

In addition to the well-known and well-despised Dandelion, these are the Top 10 Most Wanted weeds typically found causing problems in your lawn!

Crabgrass

Great for feeding livestock and fast-growing, it was once even harvested as a grain crop. Intentionally introduced into the U.S. in 1849 by the U.S. Patent Office as a livestock forage crop, it now runs rampant. Growing in the form of a rosette and laying flat (prostrate) as it grows along the ground, Crabgrass (Digitaria spp.) can root at every node that touches the ground making hand pulling tricky. The stems in the middle of the rosette can turn reddish when clumps are older. When mature and going to seed, warm-season Crabgrass can grow up to 2 feet tall with a forked spray of straight seed stems like an aerial foot. 

The only way to prevent Crabgrass or annual Bluegrass from growing is to use a pre-emergent herbicide to prevent the seeds from germinating preventing the next generation. You might need to spray 2 or three years in a row to prevent all of the seeds from germinating. Easily pulled out when young or if there are a few - just be sure to grab hold of all stems and remove them completely - because they will regrow if you leave any part behind. There are plenty of herbicides specifically geared for Crabgrass that won’t hurt other grasses that can be used as the seedlings germinate. Remove flowers before profuse seeding or else the seeds can live in the ground for years and wait for conditions to be just right. 

Plant Ryegrass in heavy Crabgrass areas and keep bare spots from forming since Crabgrass despises competition. Treat with either pre-emergents or chemicals or with Crabgrass-specific weed killer. 

Sandbur

Sandbur (Cenchrus) are warm-season and warm-climate grasses with spiked seed heads that are painful to the feet of both people and pets and get caught in fur and clothing. Similar looking to Crabgrass, Sandbur grows almost prostrate for most of its life cycle. The difference is revealed once the plants are in seed, and green burs form atop taller stems. Native to many locations around the world, they prefer sandy soil and arid climates to grow best.

Control is easy by maintaining a dense healthy turf area. Prevention involves using a pre-emergent herbicide, or post-emergent herbicide when seedlings are young. Maintaining a dense lawn to choke them out early by way of competition. This is because Sandbur prefers dry open and sandy locations that patchy lawns provide. Regular mowing, irrigation, and maintenance keep a dense turf that these plants despise.

Sedges

Also known as Nutsedge (Cyperus spp.), and Yellow or Purple Nutsedge, Sedges are native grasses that can be quite ornamental, but also native varieties can be pesky nuisances in moisture-loving locations. Easily identified by their unique triangular stems and bright green, smooth leaves. Called ‘nut’ sedges because of the nut-like tubers that form underground and help them spread, these weeds shoot up bright yellow or red/purple spiky plumes in late summer and fall (depending on the variety).

Hand pull before the Fourth of July to prevent the nutlets from forming and before they can go to seed, otherwise try to improve drainage of the area, and kill the underground tubers by digging up the entire plant methodically to keep them from coming back. A landscape fabric chokes them out well too.

Bermudagrass

Bermudagrass or Bermuda Grass (Cynodon dactylon) is a great type of turf that was widely used because of its heat, drought, salt, and foot traffic tolerance, but it’s also become a bit of a problem in and of itself. A warm season and warm climate grass, Bermuda Grass was introduced to North America from Eastern Africa in the 1800s as pasture grass. It can easily become a nuisance in garden beds and borders as it creeps into areas you don’t want them to.

Similar looking and creeping along like Zoysia grass and Japanese Knotweed, the underground stolons look similar to tiny ginger roots. Bermuda Grass creeps and spreads quickly forming dense mats that choke out other plants and turf. Keep it out of trouble with regular lawn edgers to keep it in bounds, systemic lawn herbicides, and glyphosate weed killers if needed. Smothering is one method of eradication and hand-digging it out is great for small areas of removal, but be sure to remove as much of the roots and some of the soil around the roots because of how easily they grow from the smallest bits left behind.

Bentgrass (Creeping)

Creeping Bentgrass, or Bentgrass for short, is a cool-season perennial grass that grows fast and can tolerate being mowed very short, making it great for golf courses. Thriving in cool weather and moist conditions, the light green grass has a fine texture and grows fast. Quickly overtaking other grass and choking it out. Since it is a cool-season grass, it tends to turn brown in hot weather, allowing other weeds to gain a foothold in the bare patches it creates. Bentgrasses most likely naturalized by spreading from southern Canada and now flourishes throughout most of the States.

The rapid spread can be controlled by simply improving the drainage of your soil and watering a bit less often in the spring but watering deeply when you do. Aerate your lawn regularly because Bent Grass has very shallow-growing roots that form dense mats of thatch but dry out easily with deep, infrequent waterings and when exposed to the air. Applying glyphosate and reseeding is good for small areas, but larger areas just need removed entirely and reseeded or have sod or grass plugs installed.

Foxtail Grass

Usually found in the western portions of the United States, Green Foxtail (Setaria viridis) is a grassy native weed that can irritate skin and even cause pets serious issues if they get them in their skin, eyes and nose, and even if eaten. The pretty, silky, long-tasseled seed heads resemble their namesake, looking more like bottlebrushes once the seed heads dry out. Growing in light green upright clumps, the seed heads wave in the wind along roadsides and pastures. 

Best controlled with pre-emergents, mowing frequently, and preventing bare spots from forming in the first place.

Quackgrass

Quickgrass or Quackgrass (Elymus repens) is a rough-bladed, perennial grass, that feels burred, rough, and scratchy when rubbed the wrong way. Also known as Couch grass, Dog grass, and Witch grass, this quick-sprouting, cool-season grass can be difficult to eliminate. Now considered naturalized here in the States, it was most likely brought over by settlers in their livestock feed, plant soil, and in boot treads. Alternating short seed heads with yellowish ‘flowers’ dangling off of them, they go to seed quickly and the stems break easily, making it difficult to remove by hand, quickly regrowing from broken stems and thick white roots. 

The roots and rhizomes can emit a chemical into the soil like Black Walnut trees inhibiting other plants from growing around them. Boiling water, selective types of herbicide, pre-emergents, and methodical maintenance are the best ways to stop Quack Grass. Keep a thick, lush lawn and deep waterings that are less frequent, plus weekly weed checks to catch issues before they spread far and wide. 

Clover

White Clover, Dutch Clover, Red Clover, Strawberry Clover, Yellow Sweet Clover, and more, are all members of a cold-hardy, fast-growing, and highly adaptable native wildflower that has become a widely used, eco-friendly alternative lawn plant and groundcover because of its ease of care and ability to choke out other weeds. Staying green without any fertilizer because of how these plants make their own nitrogen! They require little mowing and most grow low to the ground. The downside is that Clover doesn’t do well with lots of foot traffic. However, the very benefits that are so sought after as lawn alternatives make Clover a formidable opponent in regular lawn turf!

The pretty blooms are a bee’s favorite because of how early they emerge, often the first food source for pollinators in the spring, so be sure to treat for Clover later in the season when there are more options available for bees to sip. 

Control unwanted Clover by hand pulling, raising your mower height so your turf shades out the Clover, and by keeping your turfgrass healthy and the thatch thick to stop Clover from spreading. There are many Clover-specific herbicides.

Black Medic 

Similar looking to Clovers in leaf and bloom, Black Medic (Medicago) is a dense growing, yellow-flowering plant that grows low rosettes. Choking out other plants with their dense growth and thick colonies, these plants also make their own nitrogen as Clovers do. Introduced to North America in the late 1700s-1800s, it most likely arrived mixed in animal forage seed or inadvertently carried by settlers in crop seeds.

Using pre-emergents to stop new plants from forming in the spring is the best control method. Broadleaf weed killers, specific herbicides, and hand-pulling work well on older plants and it is important to get them before they go to seed. And a single plant can produce up to 6,600 seeds!

Moss

Dense and shading out everything else, Mosses typically have little competition due to their ability to thrive in barren, rocky, sandy, compacted, and poor soil. Moss is found on every continent of the world and grows everywhere except near salt water. Also thriving in high moisture and in the shade, or in areas that are always damp or have no drainage. Solve that and you get rid of the Moss. Many homeowners with those adverse soil conditions actually encourage Moss to grow, it has become a lawn alternative for those who cannot do anything about the condition of their soil and still enjoy a green landscape.

Improve your soil texture, loosen compacted soil, combat the acidity, and improve drainage and you’ll get rid of Moss. Spread a new layer of native topsoil and apply sod or new grass plugs to create a new lawn over the problem area. Moss grows in the shade so if your lawn area is simply too shaded you may consider using moss instead of any turfgrass!

Tips When Spraying for Weeds

So now that you have identified your lawn problems, and have opted for spraying your weeds, follow a few words of advice to do so safely.

Be sure to set your lawn mowing height to a taller height - more in the range of 3 inches or so if possible that will help to shade out some of the shorter weeds that might find their way into your lawn. It is always best to spray your lawn for weeds in later summer to eliminate all of the perennial weeds and eliminate the spring-sprouted seedlings before fall ends. This will prevent the weeds from setting seed in spring and spreading throughout your lawn. 

Late August or September on actively growing lawns that have been watered from rain or from irrigation. Be sure to pick a day to spray weed killer when your grass is dry to the touch, and rain is not forecasted for 24 hours.

Today there is an assortment of various combinations of 2 4-D, Glyphosate, MCPA, MCPP, and Dicamba weed killers that control broadleaf weeds. Boiling water, salt spot treatments, and vinegar are more natural methods, but they will also kill good plants with the bad.

Spraying Reminders 

• Always read the product's label, application directions, and reapplication requirements!
• Remember to spray only on overcast days when you do not expect rain before the spray can dry. Rain after spraying simply washes off the product.
• Try not to spray on windy days (a mythical day here in the Midwest!)
• Don’t spray when temperatures may exceed 80°F (26-27°C) you may burn leaves and blooms.
• Avoid spraying when pollinators are active during the day. 
• Keep pets and kids away during and after spraying - until the product dries or what is recommended on the product's label.
• Keep yourself safe while spraying

Also, try to only spray during times when bees and other beneficial insects aren’t as active. (Shady days, before the sun is up fully or after the sun has set, during cooler temperatures) Try to let the Clover and Dandelions bloom early in the spring so that early emerging pollinators have something nectar-rich to eat, and treat the lawn later in the growing season when there’s more variety for them to forage.

Spraying 101

The first step to spraying for weeds is to have the proper equipment:

• A well-labeled refillable sprayer or ready-to-use formula
• A garden hose that’s long enough (spray on formulas)
• A mixing tub if needed
• The spray itself - Read Those Directions!
• Protective clothing that covers all skin surfaces and your head/hair
• Eye protection 
• Mask/Breathing protection
• Footwear that the spray won't soak into

This applies to both organic and synthetic sprays since none were designed for our skin, eyes, or for breathing.

Other Methods of Control

Shade them out! Smaller areas can be killed off by covering the affected areas with black plastic, felt paper, wood boards, or cardboard until the weeds are dead. This will kill ALL plants that are shaded, including both desirable and undesirable perennial grasses, so use this option as a last-ditch genocide method. The resulting rich, black earth under the cover has essentially been composted. This may take several weeks and may not kill all weed seeds (which can tolerate higher temperatures and lay in wait for years). The killed areas will need to be tilled and reseeded or sodded after.

They’re Not The Bad Guys Here

The thing of it is, both native and invasive weeds are just doing what nature intended! Some are just a bit better at it than others, and some natives are just prettier so they get a free pass in the garden. Those that have not earned the ornamental landscape plant badge of approval for our gardens became villainized and unwanted, but it doesn’t mean they’re not important components to the ecosystem.

Nature Hills has developed Plant Sentry™ proprietary software to ensure all our plants are compliant with State and Federal Agricultural laws throughout the entire continental US. Plant Sentry prevents the sale and shipment of plants that are restricted in each state because of insects, disease, or invasiveness.

This hopefully helps keep these pesky lawn weeds from entering your area and spreading more than they already have! Nature Hills is watching out for our shared environment!

Learning to live hand in hand with our environment, leave some food for the bees, and a place for the weeds to grow, all while keeping up appearances with the neighbors is a delicate balancing act! Using a ‘take some, leave some’ approach and controlling plants brought over from other countries and even other States is what will keep our native plants - and weeds - safe from invaders of all kinds.

Create an area in your landscape where the weeds, pollinators, and native wildflowers can live life to the fullest and still keep your lawn up to par with the HOA with these preventative and control methods for your turf. That way the grass will be greener on the other side for all!

Happy Planting!