Controlling weeds and grass in large yards or acreages can feel like an impossible task. Left unchecked weeds spread aggressively stealing water and nutrients from desired plants. Finding the right weed and grass killer is key to reclaiming overgrown areas and keeping them maintained. With so many products on the market, choosing the best option for your needs takes some research. This comprehensive guide covers everything you need to know to select an effective weed and grass killer for large areas.
Types of Weed and Grass Killers
There are two main types of weed and grass killers:
Non-Selective (Broad-spectrum)
- Kills all plant types
- Glyphosate is the most common active ingredient
- Works by being absorbed through foliage
- Moves throughout the entire plant to the roots to kill completely
- Brands like Roundup, Compare-N-Save, RM43
Selective Herbicides
- Targets specific weeds and grasses
- Won’t harm desired plants like flowers, vegetables, shrubs if used properly
- Pre-emergent and post-emergent options available
- Active ingredients like 2,4-D, MCPA, dicamba
- Brands like Spectracide, Preen, Scotts
Key Considerations When Choosing a Product
With a basic understanding of the main types of weed and grass killers, next you need to consider a few key factors to select the best product for your situation:
Area Size
- Concentrated formulas cover more ground when mixed with water
- Check product labels for coverage in sq. ft. when diluted
- Larger areas need high concentrate, multi-gallon containers
Application Method
- Ready-to-use sprays for small areas
- Concentrates need tank sprayer, spreader, etc.
- Match product to equipment you already have
Timing
- Pre-emergent prevents new weeds
- Post-emergent kills existing weeds
- Non-selective works anytime but avoid hot weather
Persistence
- Pre-emergent residuals last 30-90 days
- Some post-emergents offer extended control
- Determine how long you need weed prevention
Desired Results
- Non-selective for total control of all vegetation
- Selective for control of specific weeds in lawns, beds, etc.
- Consider surrounding vegetation you want to preserve
How to Apply Weed and Grass Killer for Best Results
With the right product selected, next you need to focus on proper application for maximum effectiveness:
- Read and follow all label directions carefully
- Spray when weeds are actively growing and not under stress
- Avoid windy conditions to prevent drift to non-target plants
- Use a consistent spray pattern and appropriate pressure
- Spray foliage thoroughly until wet but not dripping
- Perennial weeds may need repeat applications
- Allow specified time before replanting in treated areas
- Wear proper protective equipment like gloves, eye protection
- Clean equipment thoroughly when finished
Top Weed and Grass Killer Product Recommendations
With an understanding of the various options and how to apply them, here are my top picks for the best weed and grass killers for large areas:
Overall Best: Roundup Weed and Grass Killer Concentrate
- Non-selective and fast-acting
- Glyphosate formula
- Visible results in 2-4 days
- Up to 6 month residual
- Rainproof in 30 minutes
Best Selective: Spectracide Weed Stop for Lawns
- Selective post-emergent
- Safe for many lawn grasses
- Results in 3-6 hours
- Kills common weeds like dandelions, clover, chickweed
Best Value: Compare-N-Save Grass and Weed Killer
- Budget-friendly cost per gallon
- 41% glyphosate concentrate
- Treats up to 25,000 sq.ft.
- Requires mixing and spraying equipment
Best Pre-Emergent: Preen Extended Control Weed Preventer
- Granular pre-emergent application
- Controls weeds up to 6 months
- Covers over 5,000 sq.ft.
- Safe for established plants and shrubs
Best Organic: Green Gobbler 20% Vinegar Weed & Grass Killer
- Natural acetic acid formula
- Non-selective, contact kill
- Safe for people, pets when dry
- Results in hours, repeat applications likely needed
Controlling weeds and grass in expansive yards, acreages, and non-planted areas takes the right combination of product choice and proper application technique. Use this guide to understand the various options and make the best decision based on your specific needs. With a little time and effort, you can get large areas under control and keep them maintained weed-free all season long. The satisfaction of seeing a beautifully manicured landscape where weeds once flourished makes it all worthwhile.
Control Weeds with Roundup®
Roundup® Dual Action Weed & Grass Killer Plus 4 Month Preventer
Kills existing weeds and grass down to the root and prevents new weeds from growing for up to 4 months.
The Best Weed Killer / Total Vegetation Control RM43
FAQ
What is the best way to kill a large area of weeds?
You can kill many weeds with vinegar. Heat (blowtorch, or specialized weed killing torches using flame or steam), roundup (glyphosate), weed block fabric, or even cardboard/newspaper Will work, too.
What is the strongest weed and grass killer that kills everything?
A. One of the strongest and most effective weed killers available is glyphosate-based weed killer.
How do you kill large areas of grass?
The best way to kill grass: 1) rototill it to loosen roots and turn them sideways or up. 2) Pull as much grass from the soil as possible while it’s tilled up. 3) Cover the soil with several layers of biodegradable cover, such as cardboard (with tape stripped off) or full sections of newsprint.