The Ultimate Guide to Controlling Weeds in Your Lawn

Weeds — every homeowner's worst enemy when it comes to achieving a lush, green lawn. Just when you think your yard is thriving, those pesky invaders pop up, spreading fast and stealing nutrients, water and sunlight from your grass. The result? Patchy, weak turf that looks anything but vibrant.

Beyond being an eyesore, weeds can also attract pests making it even harder for your lawn to flourish. Left unchecked, they’ll quickly take over, turning your dream yard into a frustrating battleground.

At TruGreen, we know how tough it can be to keep weeds at bay. That’s why our expert weed control solutions are designed to stop weeds in their tracks — so you can enjoy a healthier, greener lawn without the constant fight. 

By competing for nutrients, water and sunlight, weeds weaken your grass, leading to patchy areas and making your lawn more vulnerable to further invasion. Some weeds even attract pests or drain essential nutrients from the soil, affecting overall lawn health. Left unchecked, they can spread rapidly, taking over your yard before you know it.

Effective weed control is essential — not just for protecting your lawn’s health but also for maintaining its beauty. A weed-free lawn isn’t just healthier; it looks better, too. 

Weeds thrive when lawns are weak or in a challenging environment. Common reasons include:

• Thin or sparse grass, which leaves room for weeds to take hold
• Scalping the lawn or mowing at an incorrect height, causing grass stress and encouraging weed growth
• Overwatering, creating excess moisture that also encourages weed growth
• Too much shade, preventing grass from growing thick and strong
• Compacted soil, limiting oxygen and root development
• Low soil fertility, making it harder for grass to compete

A thick, healthy lawn is the best defense against weeds, naturally crowding them out before they can spread.

Preventing weeds before they take root is the most effective way to maintain a healthy lawn. By adopting proper lawn care practices, you create an environment where healthy grass thrives and unwanted weeds struggle to gain a foothold. Here are some essential strategies to keep your lawn weed-free:

Mowing Techniques to Discourage Weed Growth

Proper mowing is essential for maintaining a healthy, weed-resistant lawn. When mowed at the correct height, grass becomes dense and robust, preventing weed seeds from receiving sunlight, water and nutrients which would lead to them germinating. Follow these key mowing techniques to keep weeds at bay:

• Set the Right Mowing Height: Avoid cutting grass too short, as this stresses the lawn and exposes soil to weed invasion. Generally, cool-season grasses should be kept at 2.0 to 4 inches, while warm-season grasses thrive at 1 to 3.75 inches depending on the species.
• Maintain Sharp Mower Blades: Dull blades tear the grass rather than cutting it cleanly, weakening the lawn and making it more vulnerable to weeds.
• Mow Regularly: Frequent mowing encourages thicker, denser growth, which naturally crowds out weeds. To avoid stress, never remove more than one-third of the grass blade in a single mowing session.
• Leave Grass Clippings: Instead of bagging them, allow grass clippings to act as natural mulch, returning nutrients to the soil and helping prevent weed seed germination.

Mowing Tips for Warm- vs. Cool-Season Grasses

Different grass types require specific mowing approaches:

• Warm-Season Grasses: In regions where warm-season grasses go dormant, mow slightly shorter at the start of the season to promote early spring growth. Be cautious not to scalp the lawn, as this can damage grass crowns.
• Cool-Season Grasses: At the first and last mow of the season, trim slightly shorter than the recommended height to remove dormant blades and encourage a healthy spring green-up. Again, avoid scalping to prevent crown damage.

By following these mowing best practices, you’ll create a thick, healthy lawn that naturally resists weed growth.

Watering Practices for a Thriving Lawn

Proper watering strengthens grass, making it more resilient against weeds. Overwatering creates damp conditions where weeds thrive, while shallow watering weakens grass, allowing weeds to take hold. Follow these best practices to keep your lawn lush and weed-resistant:

• Water Deeply and Infrequently: Encourage deep root growth by watering about 1-2 inches per week in longer, less frequent sessions. This strengthens grass, making it harder for weeds to compete.
• Avoid Overwatering: Excess moisture promotes weed growth, soil compaction and fungal issues. Adjust your watering schedule based on rainfall and soil moisture levels.
• Water in the Morning: Early watering minimizes evaporation and allows grass to dry during the day, reducing the risk of disease and weeds that thrive in damp conditions.
• Prevent Shallow Roots: Frequent, light watering weakens grass, making it more susceptible to weed invasion. Instead, let the topsoil dry out between waterings to encourage deeper roots.
• Seasonal Adjustments: In spring and fall, rely more on natural rainfall to avoid overwatering. In summer, monitor for drought stress, but avoid excessive watering that can promote weed-friendly conditions.

Lawn Fertilization and Soil Testing

A well-nourished lawn is less inviting to weeds. Fertilization and soil testing are crucial for maintaining optimal lawn health:

• Regular Soil Testing: Conduct a soil test to identify nutrient deficiencies and imbalances. Understanding your soil's pH and nutrient levels allows for precise fertilization, promoting healthy grass growth.
• Balanced Fertilization: Apply a lawn fertilizer tailored to your grass type and soil needs. Proper fertilization strengthens your grass, enabling it to crowd out unwanted weeds.
• Follow a Fertilization Schedule: Timing is essential. Fertilize during the appropriate seasons to support your grass's growth cycle. Over-fertilizing or fertilizing at the wrong time can harm your lawn and encourage weed growth. 

Even with preventive measures, weeds can still appear in your lawn. Implementing effective control methods is essential to eliminate weeds and restore your lawn’s health. Here are some proven strategies:

Selective vs. Non-Selective Treatments

• Selective: These target specific weeds, such as broadleaf weeds like dandelions, without harming your grass. They're ideal for controlling weeds within your lawn.
• Non-Selective: These kill all plants they contact, including grass. Use them for spot treatments or clearing areas like driveways or other areas where you don’t want vegetation. Be cautious to avoid damaging your lawn.

When and How to Use Treatments

• Pre-Emergent: Applied before weed seeds germinate, these create a barrier in the soil to prevent weed growth. Apply in early spring or fall for warm-season grass lawns, depending on the weed type. If you have cool-season grass and it’s being seeded or overseeded in the fall, pre-emergent should NOT be applied. Pre-emergent for cool-season grass lawns should typically only be applied in the spring.  
• Post-Emergent: These target existing weeds. They work best when weeds are young and actively growing. Follow manufacturer instructions for the best results and safety.

Timing of Weed Control

• Pre-Emergent: Must be applied before seeds germinate, typically in spring or fall.
• Post-Emergent: Applied throughout the year to target weeds that have already appeared. 

Weeds can quickly take over a lawn, competing for nutrients, water and sunlight. TruGreen offers expert weed control to keep your lawn healthy and vibrant. Here’s how we help:

• Expert Weed Identification: Our specialists recognize various weed types and apply the most effective treatments.
• Customized Plans: We tailor solutions to your lawn’s unique needs, ensuring optimal results.
• Trusted Care Solutions: Using the latest techniques, we control weeds before they spread and eliminate existing ones.
• Comprehensive Lawn Care: We also offer fertilization, aeration and pest control to promote healthy grass growth.

Ready for a weed-free lawn? Contact TruGreen for a personalized plan today!