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How to Use Ortho Weed B Gon Max Plus Crabgrass Control

By Joshua Duvauchelle ; Updated September 21, 2017

Ortho Weed B Gon MAX Plus Crabgrass Control is a non-systemic herbicide. Unlike systemic herbicides, the product is formulated to target specific plants and is designed for use in lawns to control more than 200 types of weed species, including crabgrass. Ortho manufactures three versions of the herbicide: a ready-to-spray version, a concentrate and a ready-to-use formula.

Ready-To-Spray Product

Shake the bottle of herbicide to thoroughly mix its internal chemicals. This version of Weed B Gon Max is ideal for gardeners who need to cover a large area but don't own a garden sprayer nor want to hand-mix the concentrate.

Attach the back end of the bottle's built-in sprayer with a standard garden hose and turn on the water.

Aim the bottle of Weed B Gon Max at the area of your lawn that you wish to treat. Pull back the bottle's top plastic tab to break its internal seal, and turn its top knob to the right so it's pointing to "On." The water will shoot through the bottle from the hose and out the bottle's built-in sprayer, automatically diluting the concentrate.

Move the bottle back and forth to evenly mist your entire lawn. When finished, turn the top knob to the left to point to "Off" and turn off your water.

The Concentrate Product

Open the bottle of Ortho Weed B Gon Max concentrate. The concentrate product is typically cheaper than the ready-to-spray or pre-diluted ready-to-use formula, and is best for people on a budget and who own a garden tank sprayer.

Pour 2.4 ounces of the herbicide concentrate into the garden tank sprayer.

Add 1 gallon of water. Close the sprayer and shake it to mix the contents.

Spray the herbicide onto your lawn anywhere you notice weeds.

The Ready-to-Use Product

Turn the nozzle of the Weed B Gon Max's ready-to-use bottle to the "Open" position. This version of the herbicide is pre-diluted and ideal for spot-treating weeds.

Aim the bottle at the weeds you wish to kill. Squeeze the bottle's trigger to shoot out a coarse mist of herbicide. Evenly coat the weed.

Close the bottle's nozzle after treating your weeds to prevent spillage.


Things You Will Need

  • Water hose
  • Garden tank sprayer


  • Retreat your lawn 14 days after the initial treatment to kill any hardy weeds or plants that you may have missed.


  • Ortho's Weed B Gon Max can be used on most grass species, except for St. Augustine grass, centipede grass and Bahia grass.

About the Author


Joshua Duvauchelle is a certified personal trainer and health journalist, relationships expert and gardening specialist. His articles and advice have appeared in dozens of magazines, including exercise workouts in Shape, relationship guides for Alive and lifestyle tips for Lifehacker. In his spare time, he enjoys yoga and urban patio gardening.