Unwanted grass invading your flower beds can be a frustrating sight. Ortho Grass B Gon Garden Grass Killer is a selective herbicide designed to target grassy weeds without harming your broadleaf plants. But to get the best results, you need to apply it correctly. This guide covers everything from how it works to step-by-step application, safety precautions, and common mistakes to avoid.
What Is Ortho Grass B Gon and How Does It Work?
Ortho Grass B Gon is a post-emergent herbicide that contains the active ingredient sethoxydim. It works by being absorbed through the leaves of grassy weeds, then moving to the growing points to stop growth. It is selective, meaning it kills grasses but does not harm most broadleaf plants, flowers, shrubs, and trees. However, it will damage or kill other grasses, including lawn grasses, so avoid overspray onto your lawn.
Step-by-Step Guide to Using Ortho Grass B Gon
Follow these steps for effective application:
Step 1: Identify the weeds. Make sure the unwanted plants are grasses (e.g., crabgrass, foxtail, quackgrass) and not broadleaf weeds. Ortho Grass B Gon will not kill broadleaf weeds.
Step 2: Choose the right time. Apply when weeds are actively growing, usually in spring or early summer. Avoid application during drought or extreme heat. The ideal temperature is between 60°F and 85°F.
Step 3: Prepare the sprayer. If using a ready-to-use spray bottle, simply twist the nozzle to the spray setting. For concentrate, mix according to label directions—typically 6 fl oz per gallon of water for spot treatment.
Step 4: Protect desirable plants. Shield ornamental plants with cardboard or plastic if you are spot spraying near them. Even though the product is selective, overspray can cause damage if it contacts leaves.
Step 5: Apply evenly. Spray the grass weeds thoroughly, covering all leaves until wet but not dripping. Avoid spraying on windy days to prevent drift.
Step 6: Wait and reapply if needed. You should see yellowing and wilting within 1–2 weeks. Some tough grasses may require a second application after 2–3 weeks.
Key Buying Parameters and Product Options
Ortho Grass B Gon comes in two main formulations: ready-to-use (RTU) spray bottle and concentrate. The RTU bottle is convenient for small areas and spot treatments. The concentrate is more economical for larger gardens. When buying, check the label for the specific grass types it controls—most annual and perennial grasses are covered. Also note that it is not effective against sedges or rushes. For garden beds, the concentrate allows you to mix only what you need.
Common Mistakes and How to Avoid Them
Mistake 1: Applying to wet grass. Rain or dew can dilute the herbicide, reducing effectiveness. Apply when the grass is dry and no rain is expected for at least 2 hours.
Mistake 2: Over-spraying onto lawn. Even a small amount can kill your lawn grass. Use a shield or spray carefully. If you accidentally get some on the lawn, rinse immediately with water.
Mistake 3: Applying to stressed grass. Weeds stressed by drought, heat, or cold are less likely to absorb the herbicide. Water the area a day before if soil is dry, but let the grass dry before spraying.
Mistake 4: Expecting instant results. It takes time for the herbicide to work. Do not reapply too soon; wait at least 2 weeks.
Real-World Tips for Best Results
For stubborn perennial grasses like Bermuda grass or quackgrass, apply Ortho Grass B Gon when the grass is actively growing and has at least 4–6 leaves. Adding a non-ionic surfactant (a few drops per gallon) can improve coverage and absorption. Always read the entire product label before use—it contains important safety and usage information. Store the product in a cool, dry place away from children and pets.
Frequently Asked Questions
Q: Can I use Ortho Grass B Gon in vegetable gardens?
It is labeled for use in ornamental gardens, not vegetable gardens. Do not apply to edible plants.
Q: How long after application can I plant flowers?
There is no waiting period for planting ornamentals, but avoid spraying new transplants until they are established.
Q: Will it kill bamboo or ornamental grasses?
Yes, it will kill most grasses, including ornamental varieties. Avoid spraying any grass you want to keep.
Q: Is it safe for pets?
Once the spray has dried, pets can safely re-enter the area. Keep them away during application.
Final Thoughts
Ortho Grass B Gon is a powerful tool for maintaining weed-free garden beds. By following the steps above and avoiding common pitfalls, you can effectively eliminate grassy weeds without harming your flowers. Remember to always read and follow the product label for the best and safest results. Happy gardening!