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How to Kill Onion Grass Quickly and Effectively? (2023)

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Onion grass can be a stubborn weed that takes over your lawn. It spreads quickly and reproduces beneath the soil, making it difficult to get rid of. To kill it for good, you need to know how to identify it and what techniques work best.

In this article, we’ll show you how to do just that. We’ll take a look at some of the most effective methods, like pulling it out by hand or using herbicides like glyphosate. We’ll also discuss prevention methods, so onion weeds don’t have a chance of taking over your yard in the future!

With the right approach, you can get rid of onion grass and keep it gone for good.

What Does Onion Grass Look Like?

how to kill onion grass
Do you know what onion grass looks like? It’s an invasive weed that can wreak havoc on your lawn, so it’s important to identify it.

It has thin, waxy spear-shaped leaves and white bulbs at the base of the plant. Plus, when mowed or touched, it gives off a strong garlic or onion scent – two telltale signs it’s there.

Identifying Onion Grass

Identifying onion grass is important for successful removal. It has thin, waxy spear-shaped leaves and white bulbs that can be easily mistaken for other weeds. To differentiate, look closely at the shape of the leaves. Wild onion has flat, non-hollow leaves, and wild garlic has round hollow stems.

Its shallow root system makes it easy to remove with a weeding fork or trowel if dealt with quickly before reseeding. A selective weed killer may help control spread, but if an invasion is large, a non-selective herbicide like glyphosate might be necessary.

Cultural practices and prevention strategies, like fertilizing your lawn regularly, can help alleviate future problems from invading weeds naturally without chemicals when done correctly.

This transition into understanding Onion Grass will help create effective long-term solutions by studying its biology further. Mastering pesky garden intruders is a journey!

Characteristics of Onion Grass

Wild onion weeds have thin, waxy spear-shaped leaves and white bulbs. Wild garlic has round, hollow leaves, while wild onion has flat, non-hollow ones.
They thrive in a variety of soil conditions, including heavy wet soil, and are cold and drought hardy.
They usually appear during cooler parts of the year, such as fall, so keeping mowing habits consistent is key for prevention.

Herbicides or natural solutions can be used to eliminate this weed. Take safety precautions when using powerful herbicides, as they can lead to skin irritation if not handled properly. Glyphosate can provide an efficient solution, but must be applied twice yearly – once late fall, then again late winter – in order for it to work effectively without affecting other plants.
Make sure no one steps foot onto the area after applying until it’s fully dry.

The Best Ways to Get Rid of Onion Grass

The Best Ways to Get Rid of Onion Grass
You’re looking for the best ways to get rid of onion grass? Pulling out the bulbs by hand is a good place to start. Herbicides can also be used. Applying glyphosate with a flattened cardboard box is often effective.

Eradicating seedlings with plant killers like glyphosate requires precision, so using a combination of techniques might be necessary for optimal results.

Pull It Out by Hand

Pulling onion grass out by hand can be an effective way to get rid of it, but you’ll need a weeding fork or trowel and lots of patience. Start by watering your lawn deeply and keeping it mowed at the proper height for the type of grass you have. This helps maintain soil moisture while making sure that weeds don’t take over from healthy turfgrass plants.

You also want to keep a thick layer of mulch around any perennial beds to control wild onions, garlic, and other weeds from spreading into your lawn areas. Use the tool of choice–either a weeding fork or trowel–to dig deep enough so you remove the visible growth above ground as well as its entire root system (cormlet) below ground. Pull it up completely and discard it in a trash bag right away. This ensures no air-borne seeds spread throughout your garden again.

With diligence comes success. Keep checking regularly for new weed seedlings ready to pop up, especially during cooler seasons like late fall/winter. Applying glyphosate twice a year is also recommended as a preventive measure against future infestations.

Use Herbicides

If you’re looking to take care of onion grass quickly, herbicides are a great option. Applying chemical herbicide is the most effective way to eliminate an infestation. You need to make sure that when applying the herbicide, it is done in a precise manner with proper safety precautions. Wear protective clothing and use face masks during application. Adjust the fan setting on your sprayer so that only enough product goes onto the affected area without over-applying it. This ensures maximum effectiveness and minimizes any damage from overspray or drift of chemicals onto desirable plants nearby.

Timing is essential in controlling wild onions weeds – apply them at early morning or late evening hours when temperatures are cooler and there’s less wind. This prevents droplets from blowing away before they have time to land on target areas properly.

Mulching, overseeding and hand weeding methods combined with soil testing can help too. Use these prior/in conjunction with chemical treatments for long lasting results without risking harm from petroleum-based products sitting near roots all season long.

Apply Glyphosate

To effectively control onion grass, consider applying glyphosate with a flattened cardboard box for precise application – all while keeping your eyes and skin safe from contact. Mulching, natural solutions, soil preparation and cultural control are popular removal methods for existing blades of onion grass. Glyphosate is a useful herbicide that can be used in pre-emergent applications to prevent the weed’s growth as well as killing wild onion plants already present.

Taking immediate action when you first spot the signs of an invasion is key to preventing further spread across your lawn; apply glyphosate twice yearly in late fall or winter season for best results.

Keep children and pets away from treated areas until it has dried completely – this will ensure their safety against any potential risks associated with handling strong chemicals like glyphosate!

Use a Flattened Cardboard Box

Using a flattened cardboard box is an easy way to be precise when applying herbicide, so you can quickly get rid of onion grass without worrying about hurting other plants.
De-sodding, watering strategies, mulching tips, natural pesticides, and organic fertilizers for wild onion control, paired with your flattened cardboard box and weed removal methods like white vinegar or glyphosate, make lawn maintenance achievable.
It’s important to apply the chemical correctly, so always check the instructions before use – this will help ensure any adverse effects are minimised.
Be careful where you spray, so the cardboard box ensures only weeds are affected, leaving healthy plants unharmed.

Eradicate Seedlings

Take control of your lawn and eradicate any seedlings before they have a chance to grow. Apply an effective plant killer like glyphosate. It can be in liquid or powder form, directly onto small bulblets growing from the roots of wild onion weed. You can also use it as a preventative measure when combined with other techniques: mulching, crop rotation, soil amendments, and preparing the soil for natural weeding agents like boiling water.

Persistence and vigilance will help you achieve mastery over those pesky weeds. Reap the rewards soon!

Combination of Techniques

Take charge of your lawn and tackle onion grass head-on by combining multiple techniques. Start with simple steps like mulching or composting to block weeds. If that doesn’t work, try solarization – letting the sun heat up soil temperatures and kill any existing wild garlic and onion plants. Natural predators such as chickens can be useful too; they’ll feast on small bulbs while leaving larger ones intact.

Pre-emergent herbicides are an option if nothing else works; however, using glyphosate twice a year – once in late fall and again in late winter – is often necessary for complete eradication. So stay vigilant with constant watch over your lawn during these periods!

With all these tricks combined, there’s no reason why you can’t get rid of those pesky onions once and for all!

Want an Expert Opinion?

Want an Expert Opinion?
If you’re looking for expert advice on getting rid of onion grass, contact Green Lawn Fertilizing today and they’ll help you take control. Natural remedies like pulling the bulbs in small patches and spot treatments with a non-selective herbicide or boiling water can remove this weed. Keep an eye on soil pH levels and sun exposure to aid in prevention. Glyphosate applied twice a year late fall and late winter can help. Keep kids and pets off the treated area and protect eyes & skin from contact with chemicals.

Mow regularly – this cuts tops of wild garlic before they bloom and don’t spread their seeds. Monitor soil moisture – onion weeds thrive in wet soils. Discourage growth by applying fertilizers with high nitrogen content.

With these tips from experts plus additional info online, dealing with onion grass can be easier than ever!

Don’t Hand-pull Wild Onion or Garlic

Don’t be fooled into thinking you can simply pick wild onion and garlic out of your lawn. Hand-pulling them isn’t recommended, as the bulbs left in the soil will quickly grow back, making it difficult to prevent future issues.

Mulching strategies combined with natural predators like parasitic nematodes or cultural controls such as soil prep or turf renovation may help. Applying an effective type of herbicide like glyphosate twice a year as a preventative measure (late fall and late winter) for Allium Canadense (wild onion grass) could greatly reduce its presence in your lawn.

For further information on DIY weed control guide, check out Green Lawn Fertilizing at 888-581-5296. They specialize in removing unwanted spear shaped leaves of Onion Grass from any yard!

How to Kill Wild Onion and Garlic

How to Kill Wild Onion and Garlic
If you’re looking for an effective way to kill wild onion and garlic, also known as onion grass, Ortho Weedclear Lawn Weed Killer products provide a great solution. With the Ready-to-Use formula or Concentrate product, you can easily apply it with the Dial N Spray Hose End Sprayer.

To prevent future growth of these weeds in your lawn, it’s important to keep a thick and well-fed lawn by fertilizing regularly or aerating and dethatching when necessary.

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Ortho Weedclear Lawn Weed Killer Ready-to-use

To easily spot-treat small areas of wild onion and garlic, try Ortho WeedClear Lawn Weed Killer Ready-to-Use for quick results. Mulch, raise the mowing height, use pre emergent herbicides and lay down weed barriers to reduce infestations. An initial fall application with glyphosate or Ortho Weedclear is often needed to eradicate it in late spring.

Keep kids and pets off the lawn while applying, protect eyes and skin from contact with chemicals. For larger areas, use Ortho Weed Clear Lawn Weed Killer Concentrate for better coverage.

Ortho Weedclear Lawn Weed Killer Concentrate

Experience complete weed control with Ortho Weedclear Lawn Weed Killer Concentrate, an easy-to-use solution for ridding your lawn of stubborn weeds and giving it the lush look you desire.

Cover soil with a layer of mulch before spot spraying, mow frequently to reduce seed heads from developing into mature plants and fertilize carefully in order to promote healthy growth without encouraging weeds.

Vinegar can also be used as an alternative if you’re looking for a natural remedy but be sure not to use too much as it could harm beneficial organisms living in your soil.

These simple steps and the help of Ortho Weedclear Lawn Weedkiller Concentrate will soon have you enjoying a beautiful lawn free from pesky onion grass all season long.

Ortho Dial N Spray Hose End Sprayer

Take control of your lawn with Ortho’s Dial N Spray Hose End Sprayer, an easy-to-use solution for eliminating onion grass and boasting a lush look. Plus, it can also be used in combination with organic remedies such as soil amendments or weed barriers to create an even more effective solution.

This tool is perfect for spot treatment on sunny days and mulching strategies to prevent regrowth. When using the Dial N Spray Hose End Sprayer, take precautions against contact with this strong chemical by keeping children and pets off your lawn while treating the area.

Don’t worry if you have additional questions; Green Lawn Fertilizing are here to advise on weeds of all kinds at 888-581-5296! With its help, not only will you get rid of onion grass quickly but also reduce any unwanted garlic or onion odor from ground level.

So what are you waiting for? Start taking control now!

Keep a Well-fed, Thick Lawn

Keeping your lawn well-fed and thick is the best way to stave off wild onion and garlic growth. It can help create a lush, healthy landscape that’s more resistant to weeds. Mulching, regular mowing and a watering regime based on local climate conditions should be applied to maintain good grass health.

Fertilizing options? Consider adding organic matter like compost or manure to provide nutrients during winter months when grass isn’t actively growing. A weed barrier can keep new seeds from germinating and existing ones from taking root in bulbs, which makes them easier to remove later.

Soil conditions also play an important role in controlling wild onion and garlic, so make sure you know what kind of soil you have before deciding how much water to use for optimal results in large or small patches.

If you have any questions, contact Green Lawn Fertilizing at 888-581-5296. They’re here to advise on any other lawn maintenance issues that might come up.

Using all these techniques correctly will give better results than relying on one method alone. It’ll create a strong foundation for future success against this pesky invader.

Fertilize, Aerate, or Dethatch the Lawn

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Mulch regularly to create the right environment for healthy grass growth. Test the soil every year to make sure it’s balanced in nutrients. Follow a healthy diet that includes natural solutions, like cultivation techniques, rather than relying solely on synthetic fertilizer products.

Aerate the soil with an aerator machine or manual tool. This will create pockets in which air can circulate more freely throughout the root zone – crucial for oxygenation and water absorption.

Dethatch annually, too. Rake away layers of dead leaves from above ground so new shoots can gain access to the nutrients below-ground easier. Plus, it allows rainwater better penetration into deeper levels within your turf system.

Add some extra organic material, like composted materials or wood chips (mulch), around flowerbeds. This will help retain moisture during periods without rainfall, providing added benefit to plants’ root systems.

All these steps combined are necessary when dealing with wild onion/garlic infestations. Mulching helps keep weeds at bay naturally. Soil testing ensures adequate nutrition supply is available through tailored fertilization plans. A healthy diet encourages beneficial organisms within soils, aiding plant development and moving away from chemical-dependent only solutions. Cultivation techniques, such as weeding and proper mowing, also contribute greatly towards achieving optimal results.

How to Prevent Onion Weed From Growing

How to Prevent Onion Weed From Growing
If you want to prevent onion weed from growing in your lawn, take immediate action once the first signs of this stubborn weed are seen. It can quickly spread through grass by reseeding and reproducing under the soil, so be persistent and patient.

Use a combination of techniques such as:

  • Pulling bulbs in small patches
  • Treating with herbicides or boiling water
  • Applying plant killers like glyphosate twice a year for prevention
  • Keeping children and pets off the lawn after treatment

All these steps will help greatly in controlling this undesirable plant.

Keep a Vigilant Watch

Be sure to keep an eagle eye out for any signs of onion grass – it can spread quickly if left unchecked. Mulching, using beneficial insects or soil amendments, and cultural practices like desirable plantings are all great ways of keeping the weed from taking over. Pulling the bulbs in small patches is a great place to start, so you won’t be surprised by onion grass in early summer. Be persistent and vigilant – don’t wait till you see the first signs before getting rid of them. Act fast when you find these weeds in your lawn, and you’ll be better off in the long run.

Be Persistent and Patient

Stay ahead of onion grass and don’t let it gain a foothold – be persistent, vigilant, and patient for effective weed control.

Mulch with an organic layer two to three inches thick to prevent weeds from sprouting.

Soil test every few years to inform when to fertilize with light, tailored applications of fertilizer.

Water deeply once or twice a week to encourage deep root growth.

Use a weeding fork or trowel for removal.

Treat onion grass with a non-selective herbicide or boiling water.

Create shade by planting other plants around them.

Ensure precise application when using glyphosate.

Do all this persistently over time for successful weed control.

Identification of Wild Onion Plants

Identification of Wild Onion Plants
To identify wild onion plants, look for thin, waxy spear-shaped leaves with white bulbs and an unmistakable garlic or onion smell when mowed. Wild onions and garlic are cool-season perennials that grow from underground bulbs resembling green onions or chives; they are closely related to the vegetables grown in gardens.

These weeds can thrive in a variety of soil conditions including heavy and wet soils as well as being cold-and drought hardy. It’s important to note that these weeds will continue growing throughout the winter and spring before forming aerial bulblets during late spring.

So, it’s essential to have mulching strategies on hand, along with other soil fertility tips like composting benefits for natural weed control. If there’s an infestation of Onion grass over a large area, Ortho WeedClear Lawn Weed Killer Ready-to Use or Concentrate may be necessary. But always take precautions, such as wearing protective eye gear when applying any chemical substances near your lawns at home!

Methods to Get Rid of Wild Onions

Methods to Get Rid of Wild Onions
If you’re dealing with wild onions in your lawn, there are a few options for getting rid of them. Ortho Weedclear Lawn Weed Killer can be used to spot-treat small areas. Digging out the bulbs is best for larger infestations.

Consider using a selective weed killer like glyphosate or other herbicides specifically formulated to combat those weeds.

Remember that safety should always come first when handling chemicals. Wear protective clothing and keep kids and pets away from treated areas until it has dried completely.

Ortho Weedclear Lawn Weed Killer

To keep your lawn free of wild onions and garlic, try Ortho WeedClear Lawn Weed Killer for a quick and easy solution. This herbicide alternative provides effective pre-emergent control to prevent wild onion plants from coming back.

It’s safe to use around common garden plants and neighboring plants in the area due to its low toxicity levels compared with other weed killers like glyphosate.

You can apply it directly with an Ortho Dial N Spray Hose End Sprayer, ensuring precise application without damaging nearby vegetation or creating dangerous run offs into waterways like many chemical-based weed killers do.

With proper maintenance practices like fertilizing, aerating, or dethatching the lawn regularly, you’ll have better luck at controlling future outbreaks of weeds including wild onions and garlic on your property naturally without having to resort to harsh chemicals all the time!

Digging Out the Bulbs

Digging out the bulbs of wild onions and garlic can be tedious. But it’s an effective way to ensure they don’t regrow.

Use a weeding fork or trowel to remove smaller bulb invasions. For larger ones, remove the entire root system (cormlet) and discard it in the trash.

Mulch around areas with large onion grass invasions. And set up barriers between lawns so bulblets don’t spread.

Establish watering regimes for your plants. This’ll draw out any small remaining bulbs deep underground due to dryness. It’ll also make conditions too moist for them to survive.

Natural predators like birds can pick off seedlings about to grow. Plant competition can prevent new weeds from growing if your soil’s healthy enough.

Use this combination approach for better chances against stubborn weeds like onion grass. Just make sure children and pets stay away after applying chemicals like glyphosate twice a year.

Chemical Control With a Selective Weed Killer

Take control of bothersome onion grass with the help of a selective weed killer and create a luscious lawn you can be proud of. Mow your lawn frequently, provide mulch coverage, introduce natural predators such as birds or insects to feed on the weeds, use cultivation practices like tilling soil before seeding and composting yard waste.

If these measures fail, apply a selective weed killer for quick removal. Vinegar or baking soda mixed in water may also work, but it’s not as effective, so use this option only if necessary. Follow instructions closely when dealing with chemicals and apply them at the right time – they can harm beneficial plants too.

Digging out the bulbs from deep underground will help ensure complete eradication.

Frequently Asked Questions (FAQs)

What is the best time of year to apply herbicides to onion grass?

Do you know the best time of year to apply herbicides to onion grass? It may surprise you, but the answer’s not simple. If you want your application to be most effective, timing matters! Late fall and late winter before spring are ideal. Watch soil conditions and root depth; these can affect how well the herbicide works. Try mowing at a higher height too. With careful consideration of planting depth, soil condition, mowing height, and timely applications of weed killers like glyphosate, success is within reach!

Are there any natural alternatives to using herbicides?

When it comes to getting rid of pesky onion grass, there are natural alternatives that can help. Mulching with landscape fabric or organic solutions like composting and weed pulling are popular choices. Applying natural repellents during the cooler parts of the year in early spring can help control growth and prevent reseeding. Using mulch may reduce weeds by up to 90%, making it a great way to battle onion grass without harsh chemicals.

Is there a difference between wild onion and wild garlic?

Do you know the difference between wild onion and wild garlic? Both are cool-season perennial weeds that grow from underground bulbs. Wild garlic has round hollow leaves while wild onion produces flat, non-hollow leaves. They have a strong onion or garlic smell when mowed.

They’re close cousins too; both plants thrive in a variety of soils – even heavy and wet ones – making them hardy against droughts and cold temperatures.

If you’re looking to smother your weed problem with natural remedies like deep weeding or mulching the soil around it with chemical control as a last resort, be sure to identify which one is invading your lawn first!

Is it safe to mow over wild onion and garlic plants?

Mulching, Fungicides, Smothering and Cultivating are all great ways to get rid of wild onion and garlic. But what about mowing? Experienced gardeners will tell you that the aroma of freshly cut grass isn’t so nice when it comes to wild onion or garlic. You may risk spreading their bulbs through your lawn by mowing over them. Consider Solarizing or using an easy application like vinegar. It can smother the plants and sterilize the soil where they were growing. Before you grab those blades and start humming away in your yard, make sure there aren’t any pesky weeds lurking around waiting for a free ride!

What are the long-term effects of using herbicides on onion grass?

Mowing over wild onion and garlic plants may seem like an easy way to tackle weeds, but it can actually do more harm than good. Herbcides are a popular option when dealing with invasive onion grass, however using them must be done carefully and thoughtfully.

Long-term effects of herbicides on this weed include destruction of beneficial soil fertility, compromising mulching benefits in flower beds, and slower mowing frequency due to increased growth rates resulting from weakened weed barriers.

Natural alternatives exist that take time – up to several weeks – but will ultimately result in healthier turfgrass with fewer white bulbs popping up each spring!


Don’t let onion grass take over your lawn! With the right techniques, you can easily get rid of it and keep it away for good. But it takes some effort and persistence; you’ll need to keep a vigilant watch and be patient. Don’t forget to fertilize, aerate, and dethatch your lawn to help prevent onion grass from growing in the first place.

Take a look at the diagram for an easy-to-follow visual representation of all the steps you’ll need to take to effectively remove onion grass from your lawn. With this guide, you’ll have a healthy and vibrant lawn in no time.

Avatar for Mutasim Sweileh

Mutasim Sweileh

Mutasim is a published author and software engineer and agriculture expert from the US. To date, he has helped thousands of people make their yards lush and thick.