Sedgehammer (also known as Sedgehammer Plus or Sedgehammer+), manufactured by Gowan, is a selective, post-emergent herbicide formulated with halosulfuron-methyl to control nutsedge and other broadleaf weeds. 

Sedgehammer comes in two different versions: Sedgehammer and Sedgehammer Plus.

Sedgehammer comes in a bottle and is used for treating large areas. It has a higher concentration of halosulfuron-methyl at 75%. It must be mixed with a surfactant. Sedgehammer Plus comes in pre-measured packets that are used for treating smaller areas. Each packet has a surfactant mixed in with the product and can treat 1,000 square feet. The amount of active in this version is 5% halosulfuron-methyl.

Both versions of Sedgehammer are safe weed killers in lawns mixed in water to create a spray. When applied to the leafy tissue of targeted weeds, the solution moves down to the roots to eliminate the plant. Sedgehammer is ideal to use on residential, commercial, and industrial areas.

Tools Needed

To apply Sedgehammer, a backpack sprayer, hand pump sprayer, or a professional spray rig is needed. For small volume areas, we recommend using a hand pump sprayer.

If you are using the Segehammer Nutsedge Killer 1.3 oz, you will need to use a surfactant with it such as Nanotek Surfactant.

How to Use

• Step 1: Determine how much Sedgehammer Nutsedge Killer or Sedgehammer Plus to use by measuring the square footage of the treatment area. You can do this by measuring the length and width of the treatment area then multiplying them together (length X width = square footage). Spot treatments in turfgrass with Sedgehammer Nutsedge Killer 1.3 size, use 0.9 gram of this product with in 1-2 gallons of water per 1,000 sq. ft. Add 2 tsp (1/3 fl. oz.) of nonionic surfactant per gallon of water. Broadcast applications in turfgrass with Sedgehammer Nutsedge Killer 1.3 size, apply 2/3 to 1 1/3 oz. of product per 100 gallons of water per acre. Turfgrass applications with the Segehammer Plus 13.5 gram will use 1 of the 0.9 gram water soluble bag of this product per 1-2 gallons of water per 1,000 sq. ft. You do not need to mix in a surfactant with Sedgehammer Plus.
• Step 2: After measuring the amount of Sedgehammer you will need, you can begin to create your solution. Fill your spray tank with half the amount of water, then add the measured amount of Sedgehammer Nutsedge Killer or the right amount of opened packets of the Sedgehammer Plus. If you are using the 1.3 bottle size then add the measured amount of non-ionic surfactant. Lastly, pour the remaining half of water and stir or shake thoroughly for 2 minutes until the product contents and surfactant are completely dispersed.
• Step 3: After diluting your Sedgehammer in water, you can begin applying your mixed solution. On a fan spray setting, spray the target weeds thoroughly until wet, but not to the point of runoff. A second treatment may be needed 6 to 10 weeks after your initial treatment. For best results, do not mow turf 2 days before or 2 days after application.

Where to Use

Sedgehammer Nutsedge Killer and Sedgehammer Plus can be applied to nutsedge and other weeds in established lawns, ornamental turfgrass, landscaped areas, commercial and residential turf and on other non-crop sites including: airports, campgrounds, cemeteries, fairgrounds, fence rows, fallow areas, fuel storage areas, golf courses, landscaped areas, established woody ornamentals in landscape areas, lumberyards, public recreation areas, race tracks, residential property, rights-of-way, roadsides, school grounds, sod or turf seed farms, sports fields, tank farms and tennis courts.

Do not apply either of these product to golf course putting greens, and do not spray over the top of desirable flowers, ornamentals, vegetables, shrubs, trees, or vascular plants.

When to Use

Apply Sedgehammer Nutsedge Killer or Sedgehammer Plus when weeds are actively growing and have emerged from labeled sites.

These products can be applied when the turf has not been mowed for at least 2 days before application, and do not mow 2 days after application. Do not use these products when rainfall is forecasted to occur within 4 hours of application.

When controlling nutsedges, do not apply if either the turfgrass or nutsedges are under stress.

Safety Information

Sedgehammer Nutsedge Killer and Sedgehammer Plus is safe to use around children and pets when applied according to the product label instructions. Always wear the proper personal protective equipment when mixing and applying this product.

Keep people and pets out of treated areas until the spray solution has dried.

Special Considerations

Be aware of which version of Sedgehammer you are using. Only Sedgehammer Plus contains a non-ionic surfactant. If you are using the bottled version of Sedgehammer, you will need to mix the solution with a product like Nanotek Surfactant to ensure the solution sticks to the weeds you want to control.

Do not replant sunflowers until 18 months have passed after application.