How to Fix a Lawn Full of Weeds

A well-maintained lawn serves as a centerpiece of beauty and functionality for any property. A lush, green expanse not only enhances the aesthetic appeal of your home but also provides space for recreational activities, relaxation, and social gatherings. However, an unwelcome intruder can quickly turn this picturesque setting into a distressing sight — weeds.

Common Types of Lawn Weeds

Lawn weeds are unwanted plants that compete with desirable grass species for nutrients, water, and sunlight. They can be broadly categorized into three types: broadleaf weeds, grassy weeds, and sedges. Common examples of broadleaf weeds include dandelions, clover, and chickweed, while grassy weeds encompass crabgrass and goosegrass. Sedges are grass-like weeds, such as nutsedge, that can be particularly challenging to eradicate.

Before diving into weed control strategies, it's crucial to understand the underlying causes of weed infestations. By addressing these root factors, you can create an environment that supports a vigorous, weed-free lawn. So, we will explore preventive measures and long-term lawn care practices that reduce the likelihood of weed resurgence.

Identifying Lawn Weeds

A well-informed approach to weed control begins with accurate identification. Different types of weeds require specific treatment methods, so knowing what you're dealing with is essential for effective eradication.

Understanding Different Types of Weeds

• Broadleaf weeds: These weeds have relatively broad leaves and are easy to distinguish from grasses. Examples include dandelions, clover, plantain, and chickweed.

• Grassy weeds: Grass-like weeds can be challenging to identify since they resemble desirable lawn grasses. Common grassy weeds include crabgrass, goosegrass, and foxtail.

• Sedges: Sedges look similar to grasses but have triangular-shaped stems. Nutsedge is a prevalent type of sedge found in lawns.

To help identify weeds in your lawn, check out our Complete Guide to Common Lawn Weeds and How to Get Rid of Them, which includes pictures and the best control methods for each weed.

 

Causes of Lawn Weed Infestation

A healthy and weed-free lawn requires more than just treating the visible weeds; it involves addressing the root causes of weed infestations. Understanding these underlying factors will help you create a conducive environment for a lush, weed-resistant lawn. 

1. Poor Lawn Care Practices

• Improper mowing: Incorrect mowing height or irregular mowing schedules can weaken the grass, making it more susceptible to weed invasion.

• Overwatering or underwatering: Inconsistent watering practices can stress the grass and create conditions favorable for certain weed species.

• Inadequate fertilization: Insufficient nutrients in the soil can lead to weak grass, leaving gaps that weeds quickly fill.

• Compacted soil: Soil compaction restricts air circulation and nutrient absorption, hindering the growth of healthy grass and encouraging weed growth.
  

2. Soil Imbalances and Nutrient Deficiencies

• pH Imbalance: Soils that are too acidic or alkaline can affect nutrient availability for the grass, leading to weed encroachment.

• Lack of organic matter: Poor soil structure with low organic matter content can reduce grass vigor and open up space for weeds to thrive.

• Imbalanced nutrient levels: An imbalance in essential nutrients like nitrogen, phosphorus, and potassium can negatively impact grass health and provide opportunities for weeds.

3. Environmental Factors Promoting Weed Growth

• Sunlight exposure: Areas with insufficient grass coverage that receive ample sunlight become susceptible to weed colonization.

• Shade and moisture: Shaded and damp spots create conditions favorable for certain weeds to flourish, especially where grass struggles to grow.

• Seed dispersal: Weeds produce copious amounts of seeds that can spread rapidly via wind, animals, or human activity, leading to new weed growth.
  
  

Q. Are there any benefits of having some weeds in my lawn or garden? A. Some weeds can provide habitat and food for beneficial insects, support pollinators, and improve soil health. Clover can be beneficial as it fixes nitrogen in the soil, promoting better grass growth. However, managing their presence is essential to prevent them from becoming invasive.

 

It's crucial to conduct a thorough lawn assessment to identify the specific issues contributing to weed infestations in your lawn. A soil test can reveal nutrient deficiencies or pH imbalances, while observing lawn care practices will highlight areas for improvement. Once you've addressed the underlying causes, your lawn will become more resilient to weed encroachment.

 

Preparing for Weed Control

Proper preparation is essential for maximizing the effectiveness of your weed control efforts. So before you start, take these steps to prepare for effective weed control:

1. Lawn Assessment and Planning

• Evaluate the lawn: Take a close look at your lawn to identify the extent of the weed infestation. Note the types of weeds present and the areas most affected.

• Identify problematic areas: Determine areas with thin or patchy grass, as these may require additional attention during the weed control process.
  
  
• Create a weed control plan: Based on the lawn assessment, develop a systematic approach to tackle the weeds, considering natural and herbicide control methods..
  
  

Q. What are some ways to prevent weeds in newly seeded lawns? A. Prevent weed growth in newly seeded lawns by avoiding foot traffic, keeping the area moist for germination, and using straw mulch to suppress weed growth. For cool-season grass, consider using Tenacity, which has pre-emergent properties to keep a lawn weed free for 3 - 4 weeks.

 

2. Necessary Equipment and Materials

• Weed-pulling tools: Acquire handheld weed pullers, dandelion diggers, and other manual weed removal tools for tackling individual weeds.

• Mowing equipment: Ensure your lawnmower is in good working condition, as regular mowing is crucial for preventing weed seed development.

• Gardening gloves: Wear sturdy gloves to protect your hands during weed removal and chemical application.

• Herbicides: If you plan to use herbicides, select appropriate products for the types of weeds present and follow the manufacturer's instructions carefully.

• Mulch: Purchase organic mulch materials to help suppress weed growth and retain soil moisture in flower beds.

• Fertilizer: Consider using a balanced fertilizer to provide essential nutrients to your grass and promote its health.
  
  

Q. Can I compost weeds I've removed from my lawn and garden? A. Avoid composting weeds that have gone to seed, as the seeds may survive the composting process and sprout in your lawn when you use the compost.

  

Related Reading: How to Nail Weed Management This Summer

 

3. Choosing the Right Time for Weed Control

• Early spring: Early spring is ideal for pre-emergent weed control, as it helps prevent weed seeds from germinating.

• Late spring to early summer: This period is suitable for post-emergent herbicide application to target actively growing weeds.

• Fall: Fall is the time to focus on lawn renovation, overseeding, and addressing persistent weeds before winter dormancy. Fall pre-emergent is also essential to control difficult weeds like poa annua.

• Weather considerations: Avoid applying herbicides during windy or rainy conditions, as it may lead to unintended damage or reduced efficacy.

 

 

Natural Weed Control Methods

Taking an eco-friendly and sustainable approach to weed control benefits the environment and promotes the long-term health of your lawn. Natural weed control methods can effectively manage weeds while minimizing the impact on beneficial organisms and your lawn's ecosystem. 

1. Manual Weed Removal Techniques

• Hand pulling: For isolated or small patches of weeds, hand pulling is an effective method. Ensure you remove the entire root system to prevent regrowth.

• Weed digging tools: Utilize specialized tools like dandelion diggers, weed knives, or hoes to make weed removal more efficient, particularly for tap-rooted weeds.

• Mowing practices: Regular and proper mowing at the correct height can prevent weed seed heads from developing and spreading.
  
  

Q. How often should I mow my lawn to prevent weeds? A. Regular mowing is crucial for weed prevention. For most grass types, mow at a height of about two-and-a-half to three inches and aim to mow no more than one-third of the grass blade at a time. For ideal weed control and lawn appearance, aim to mow 1 - 2 times per week..

 

 

2. Natural Weed Suppression Methods

• Mulching: Apply a layer of organic mulch, such as wood chips or straw, around plants and in garden beds to smother weeds and conserve soil moisture. 

• Proper watering: Water deeply but infrequently to encourage deep root growth in the grass while discouraging shallow-rooted weeds. 

• Overseeding: Thickening your cool-season lawn by overseeding with grass varieties appropriate for your region helps choke out weeds and create a denser, healthier turf. 
  
  

Q. Can I use mulch to prevent weeds in my lawn? A. While mulch is more commonly used in garden beds, it can be used sparingly around trees and shrubs in lawns to help suppress weed growth. However, mulch use on your lawn should be avoided.

 

Related Reading: How To Kill Weeds Naturally 

 

3. Maintaining Healthy Lawn Practices 

• Fertilization: Regularly fertilize your lawn using organic slow-release fertilizers to provide essential nutrients that support grass growth and outcompete weeds. 

• Proper irrigation: Water your lawn early in the morning to reduce evaporation and give the grass enough time to dry during the day, preventing moisture-loving weeds from thriving. 

• Aeration: Aerating the soil improves air and water penetration, promoting healthier root systems and reducing weed establishment. 

By employing these weed control methods, you can significantly reduce weed populations and create a more resilient lawn. It is best to combine multiple approaches to target different weed species and growth stages effectively. However, strategically integrating herbicide weed control methods may also be necessary for severe weed infestations or persistent weeds. 

Q. Are natural or organic herbicides as effective as chemical ones? A. Natural or organic herbicides can be effective against younger weeds. However, they may require more frequent application. For stubborn or established weeds, chemical herbicides will likely be more effective.

 

 

 

Herbicide Weed Control Options

Herbicide weed control, when used judiciously and following manufacturer guidelines, can be an effective tool for managing stubborn or widespread weed infestations. 

Understanding the types of herbicides available and their appropriate usage is essential to minimize the impact on the environment and non-target plants. 

1. Selective vs. Non-Selective Herbicides

• Selective herbicides: These herbicides target specific types of weeds while leaving desirable grass species relatively unharmed. They are effective for controlling a variety of weeds without harming the surrounding lawn. Always ensure that the herbicide is suitable for your grass type.

• Non-selective herbicides: Non-selective herbicides kill a wide range of plants, including both weeds and desirable grass species. They should be used cautiously and only applied directly to the targeted weeds to avoid damaging your lawn.
  
  

Q. What should I do if weeds are growing in the cracks of my driveway or sidewalk? A. Use non-chemical or organic methods like boiling water, vinegar-based herbicides, or manual removal to address weeds growing in pavement cracks. Be cautious with any chemicals near pavement to avoid runoff into storm drains.

 

 

2. Pre-emergent vs. Post-emergent Herbicides

• Pre-emergent herbicides: These herbicides are applied before weed seeds germinate, forming a barrier in the soil that prevents weed seedlings from growing. They are effective against annual grassy weeds like crabgrass and can be applied in early spring.

• Post-emergent herbicides: Post-emergent herbicides are applied after weeds have already emerged. They come in selective and non-selective forms and are best used when weeds are actively growing for optimal absorption.
  
  

Q. Can I use herbicides near my vegetable garden? A. Extreme caution must be exercised when using herbicides near vegetable gardens. It is best to avoid using herbicides in these areas to prevent contamination of edible crops. Instead, consider manual weed removal or using organic methods.

 

 

3. Safety Precautions and Guidelines

• Read and follow instructions: Carefully read and follow the instructions on the herbicide label, including application rates, timing, and safety precautions.

• Protective gear: Wear appropriate protective gear, such as gloves, long-sleeved shirts, long pants, and eye protection, when handling and applying herbicides.

• Keep pets and children away: Keep pets and children off the treated area until the herbicide has dried or as specified on the label.

• Calibrate equipment: If using a backpack sprayer, calibrate it accurately to ensure proper herbicide application and avoid overuse. We recommend using a foliar spray tip or a floodJet spray tip so that the product is applied evenly over the lawn. Use a foliar spray tip when the herbicide is absorbed via the plant leaf. Floodjet spray tips are used for products designed to work in the soil profile..

• Environmental concerns: Avoid applying herbicides on windy days to prevent drift onto non-target plants, and do not apply near water sources to prevent contamination.

• Proper storage and disposal: Store herbicides in their original containers, away from children and pets. Dispose of empty containers according to local regulations.
  
  

Q. Are there any pet-safe weed control methods? A. Yes. Most residential herbicides are pet-safe as long as they are given ample time to dry. Alternatively, opt for non-toxic weed control methods, such as manual removal, organic herbicides, or using physical barriers to keep pets away from weedy areas.

 

Related Reading: Safe Lawn Care Products for Pets

 

Implementing Weed Control Strategies

With a clear understanding of non-chemical and chemical weed control methods, it's time to implement a comprehensive strategy to tackle the weed problem in your lawn. Combining different approaches allows you to target various weed species and growth stages effectively. 

1. Step-by-Step Process for Weed Removal

• Identify and map weeds: Begin by identifying the types of weeds in your lawn and map out the areas with the most significant weed infestations.

• Hand-pull or dig weeds: For isolated or small patches of weeds, manually remove them using handheld weed pullers or digging tools, ensuring you remove the entire root system.

• Mow regularly: Maintain a regular mowing schedule, cutting the grass at the recommended height for your grass type. This helps prevent weed seed development and keeps your lawn healthy.

• Apply pre-emergent herbicides: If applicable for your region and weed species, apply pre-emergent herbicides in early spring and fall before weed seeds germinate.

• Apply post-emergent herbicides: For established weeds, use selective or non-selective post-emergent herbicides as needed, following manufacturer instructions carefully.
  
  

Q. Can I use black plastic or landscape fabric to prevent weeds in my garden? A. While black plastic and landscape fabric can help suppress weeds, they may also hinder soil aeration and drainage. Consider using biodegradable or permeable mulch alternatives to promote a healthier garden environment.

 

Related Reading: The Best Lawn Weed Killer for Beginners

 

2. How to Apply Pre-emergent Herbicides

Using pre-emergent herbicides requires careful application and timing to effectively control weeds before they emerge from the soil. They come in two forms: granular and liquid. Liquid pre-emergent weed killer is fast-acting, potent, and requires attention to detail to apply correctly. A floodJet spray tip should be used to apply liquid pre-emergent. Granular pre-emergent weed killer is more slow-acting and is easier to apply since all you need is a broadcast spreader.

1. Select the right herbicide: Start by choosing a pre-emergent herbicide that is suitable for the specific weeds you want to control and safe for your grass type and the of plants you have in your lawn or garden. Read the product label carefully for instructions, precautions, and the recommended application rate.
   
   
2. Determine the timing: Timing is crucial for pre-emergent herbicide application. The goal is to apply the herbicide just before weed seeds germinate, creating a barrier in the soil to prevent weed growth. The best time to apply pre-emergent herbicides varies based on your location and the type of weeds you are targeting. Generally, spring applications are performed before the average soil temperature reaches 55 degrees. Fall pre-emergent should be applied when soil temperatures are in the low 70s and trending cooler. When in doubt,  consult your local extension office to determine the ideal timing for your region.
   
   
3. Prepare the area: Before applying the herbicide, remove any existing debris like twigs or pine cones to ensure the best contact between the herbicide and the soil.
   
   
4. Measure the area: Calculate the square footage of the area you want to treat. This information will help you determine the correct amount of herbicide to apply, following the product label's recommendations.
   
   
5. Apply the herbicide: There are different types of pre-emergent herbicides, including granules and liquid formulations. Follow these general steps:
   
   
   • Granules: We recommend Dithiopyr pre-emergent in spring as it is a dual-action herbicide that prevents invading weeds and controls young crabgrass without harming your grass. It is suitable for both cool and warm-season grasses, making it versatile for various lawn types. 
     
     This granular pre-emergent targets a wide range of weeds, including dandelions, crabgrass, annual bluegrass, chickweed, and more. Use a broadcast spreader to apply the granules evenly over the target area. Walk at a steady pace to ensure even coverage.
   
   
   • Liquid: At the top of our recommended products list is Prodiamine 65 WDG (water-dispersible granule), a versatile water dispersible granule herbicide that requires mixing with water before application.
     
     This non-staining herbicide works well against a broad range of weeds helping your lawn remain pristine.  With its low solubility and volatility, Prodiamine 65 penetrates deep into the weed germination zone and stays there, delivering outstanding and long-lasting weed control for up to 4 months.
     
     Use a backpack sprayer to apply the liquid herbicide evenly over the lawn. To ensure you’ve covered the entire surface without leaving any untreated patches, use a turf mark dye indicator to show you where you’ve already sprayed the product.
     
     
6. Water the area: After applying the herbicide, both liquid and granular pre-emergent must be watered in. This helps activate the herbicide and move it into the soil, forming a barrier against weed germination.
   
   
7. Avoid disturbance: Avoid disturbing the treated area after application. Any digging, tilling, or cultivation can break the herbicide barrier and reduce its effectiveness.
   
   
8. Observe and reapply if necessary: Keep an eye on the treated area for any signs of weed growth. If you notice weed breakthrough, you may need to reapply the pre-emergent herbicide according to the product label instructions. Be cautious not to exceed herbicide active ingredient annual limits to avoid buildup in the soil.

Always read and follow the instructions on the product label carefully, as specific guidelines may vary depending on the brand and type of pre-emergent herbicide you use. Also, consider wearing appropriate protective gear, such as gloves and eye protection, when handling and applying herbicides.

 

Q. Can I use herbicides on a newly seeded lawn? A. New grass seedlings are sensitive and vulnerable. It's best to avoid using herbicides on a newly seeded lawn until the grass is well-established.

 

 

3. How to Apply Post-emergent Herbicides

Using post-emergent herbicides involves applying the herbicide directly to actively growing weeds. These herbicides are effective against weeds that have already emerged from the soil. 

1. Identify the target weeds: Before applying a post-emergent herbicide, correctly identify the types of weeds in your lawn or garden. Different herbicides target specific weeds, so knowing the type of weed you're dealing with will help you select the right product.
   
   
2. Choose the appropriate herbicide: Select a post-emergent herbicide that is designed to control the specific weeds you have and is safe for your grass type.Read the product label carefully for instructions, precautions, and the recommended application rate.
   
   
3. Check the weather conditions: Choose a day to apply the herbicide when the weather is calm, and rain is not expected for at least 24 hours. Rain shortly after application can wash away the herbicide, reducing its effectiveness.
   
   
4. Prepare the area: Remove any debris or vegetation that may interfere with the application or reduce the herbicide's contact with the target weeds before applying the herbicide.
   
   
5. Wear protective gear: Put on appropriate protective clothing, such as gloves, long sleeves, long pants, socks, and eye protection, to avoid direct contact with the herbicide.
   
   
6. Apply the herbicide: There are different forms of post-emergent herbicides, including ready-to-use sprays and concentrated solutions that need to be mixed with water. Follow these general steps:
   
   
• Ready-to-use sprays: Shake the container well and aim the spray nozzle directly at the weeds. Apply the herbicide evenly over the foliage of the target weeds, covering all plant surfaces thoroughly. Be careful not to spray desirable plants, as the herbicide can harm them as well.
  
  
• Concentrated solutions: Dilute the herbicide as per the product label instructions. Use a sprayer to apply the diluted solution to the weeds, ensuring full coverage. Use a foliar spray tip for best results.
  
  
7. Observe and reapply if necessary: After application, monitor the treated area for  7-14 days to see how the weeds respond to the herbicide. Some weeds may require multiple applications, so if you notice new growth or incomplete control, you may need to reapply the herbicide following the product label instructions. As a general rule, we recommend waiting three weeks between applications for selective herbicides.
   
   
8. Cleanup and disposal: Clean any tools or equipment used for herbicide application thoroughly after use. Dispose of any excess herbicide or empty containers according to local regulations.

Always read and follow the instructions on the product label carefully to ensure the safe and effective use of post-emergent herbicides. Avoid applying herbicides during windy conditions or near bodies of water to prevent drift or water contamination. Additionally, store herbicides in their original containers and keep them out of reach of children and pets.

 

Q. What should I do if I accidentally apply herbicide to desirable plants? A. If herbicide overspray occurs, rinse the affected area immediately with water to minimize damage. Avoid herbicide application on windy days to reduce the risk of drift.

 

Related Reading: Best Weed Killer Spray for Lawns

 

4. Tips for Managing Large-Scale Weed Infestations

• Divide and conquer: Tackle large lawn areas in sections, addressing the worst infestations first. This allows you to concentrate efforts and track progress more effectively.

• Lawn renovation: For severely weed-infested lawns, consider a complete lawn renovation, which involves killing off existing vegetation and starting anew with grass seeding or sod installation.

• Long-term maintenance: Once you've controlled the weeds successfully, implement a consistent lawn maintenance routine, including proper mowing, fertilization, and watering, to prevent weed resurgence.
  
  

Q. Should I reseed my lawn after weed control to fill in bare spots? A. Yes, overseeding your cool season lawn after weed control helps fill in bare spots and promote a dense and weed-resistant turf.

Maintaining a Weed-Free Lawn

Achieving a weed-free lawn is a significant accomplishment, but the journey doesn't end there. To preserve the health and beauty of your lawn and prevent future weed infestations, it's crucial to keep a close eye on your lawn all year round and deal with weeds as soon as you notice them. 

1. Proper Lawn Maintenance Practices

• Regular mowing and edging: Continue to mow your lawn at the recommended height for your grass type. Additionally, maintain well-defined edges along sidewalks and garden beds to prevent weeds from encroaching.

• Fertilization and soil testing: Follow a regular fertilization schedule and conduct soil tests periodically to ensure your lawn receives the necessary nutrients for optimal growth.

• Correct watering techniques: Water your lawn deeply but infrequently, ensuring that the soil receives adequate moisture without encouraging excessive weed growth.

• Aeration: Aerating your lawn annually or as needed promotes healthier root systems, better nutrient absorption, and improved water penetration, all of which aid in weed prevention.

 

2. Preventing Weed Seeds from Spreading

• Remove weeds before seed development: Regularly inspect and remove weeds before they produce seeds to prevent further weed spread.

• Catch clippings: If you mow the lawn while weeds are present, bag and dispose of the cuttings to prevent weed seeds from spreading.

• Clean tools and footwear: After working in weedy areas, clean your tools and footwear to avoid transporting weed seeds to other parts of the lawn.
  
  

Q. How do I prevent weeds from spreading from my neighbor's yard to mine? A. Create a physical barrier like a deep edging or install landscape fabric along the property boundary to prevent weed seeds from spreading into your lawn.

Dealing with Persistent and Resistant Weeds

Despite your best efforts in implementing weed control strategies and maintaining a healthy lawn, you may encounter stubborn weeds that seem unaffected by traditional methods. Persistent and resistant weeds can be challenging to manage, requiring additional measures to address effectively. 

 1. Identifying Stubborn Weed Species

• Conduct research: Identify the specific weed species causing persistent issues in your lawn. Research their growth habits, life cycles, and preferred conditions.

• Seek expert help: If you're unsure about the weed species or the appropriate control methods, consult your local agricultural extension office or a professional lawn-care service for expert advice. Google image search also works well for weed identification.

 

Related Reading: Identifying the Weeds That Could Destroy Your Lawn

 

2. Advanced Control Methods

• Spot treatments: Use a non-selective herbicide for spot treatments to target individual weeds while minimizing damage to the surrounding grass. This approach is ideal for managing persistent weeds where there are no selective means of control.

• Targeted herbicide application: Consider using a foam applicator or a paintbrush to apply non-selective herbicides directly to the leaves of tough-to-control weeds. This method minimizes herbicide drift and ensures precise application.

 

3. Seeking Professional Help

• Lawn-care specialists: If the weed infestation becomes overwhelming, consider hiring a professional lawn-care company with experience handling persistent weed problems.

• Landscape design changes: In severe cases, a landscape redesign may be necessary to remove persistent weed sources or change the conditions that favor weed growth.
  
  

Q. Do certain grass species naturally resist weed invasion better than others? A. Some grass species, such as Kentucky bluegrass and fine fescue, have better weed resistance than others. Choose grass varieties suitable for your region and lawn conditions.

 

Dealing with persistent and resistant weeds may require time, effort, and multiple approaches. Regular monitoring and consistent control measures are essential to prevent the weeds from spreading further. But you can be even more persistent in your battle to defeat the weeds!  

Weed control is an ongoing process, and new weed seeds may be introduced over time. By staying vigilant and implementing both non-chemical and chemical control methods strategically, you can enjoy a healthy and vibrant lawn.

If you’re interested in our lawn-care tips and want to learn more, check out our blog. Also, get free lawn care advice on our YouTube channel and subscribe today. If you want to go one step further, sign up for the Golf Course Lawn Academy.