The best crabgrass killer for lawns would be Reef Turf Insecticide. It’s a non-selective systemic insecticide that will not kill lawn grasses like perennial fescue, eyeglass, fescus, and centipede grasses. Reef Turf Insecticide is applied at ground level once a year. It can be used on lawns that are infested with crabgrass and on turfgrasses too. It can also be used as an over the winter treatment to kill those stubborn crabgrass that refuses to go away in the fall.
Boric acid, when sprayed in cool weather, is an effective crabgrass killer. It is not selective, meaning it will kill any crab grass that crosses its path, but it also will not kill any of the natural grass that may have grown around it. It is effective on weeds and will kill tree roots too. Boric acid is water soluble so it will dissolve quite quickly when sprayed on the ground. It does not burn the soil like some other insecticides do.
Glyphosate is an active ingredient in many weed control products. It has been found to be very effective in killing both crabgrass and black-eyed susans (also known as night crawlers). However, despite its effectiveness, it is considered a hazardous air pollutant by the EPA and State officials. Glyphosate can drift out into the atmosphere and drift into lakes, streams, and other bodies of water causing significant contamination. So it’s important to purchase weed and feed products that contain only authorized pesticides or herbicides certified as safe for use on residential gardens.
A second effective herbicide is rainproof crabgrass killers. Rainproof products are manufactured to withstand heavy downpours, yet still remain effective if the weather is light. In addition, they are designed to be planted at the base of the growing turf where the crabgrass grows to prevent it from spreading towards the ground. Brands such as DEFY Advanced Technologies, Invigorator, Andros, Orgreen, Power Logic, Ecover, and Pro Logic are available both on the internet and at retailers nationwide.
A third option is to drive xlr8 herbicide crabgrass killer which combines the effectiveness of the two previous products. These products are designed to be installed on the grass as soon as it is ready. Once the herbicide is applied, it will remain active until it evaporates from the soil, preventing it from destroying the crab grass seed. This type of crabgrass killer is approved for both commercial and residential use.
An additional solution is to use a spray tenacity turf herbicide that contains a blend of natural enemies, copper and silver ions. It prevents the growth and spread of both crabgrass seeds and its rhizomes. Brands include: Zoysia, Power Logic, Branded Crop, Invigorator, Ecover, E-Max, Branded Andros, and Bermuda grass. A spray tenacity turf herbicide is ideal for homeowners because it penetrates deeply into the soil, acting quickly, thus reducing weed growth after each application.
The best crabgrass killer for lawns with existing turf is the pre-emergent herbicides. These herbicides control both crabgrass seedling and crabgrass rhizomes, but can also prevent the germination of seeds from other species. To ensure consistent results, these pre-emergent herbicides are usually sprayed on the grass before it emerges from the ground. They can also be directly applied to turf.
The best crabgrass killers for turf must not only be effective but also be easy to apply. Most are available in liquid form, which can be dispensed with a spray gun or directly onto the grass. However, some people prefer to apply the chemicals in foam formulas, which are more persistent. Other sprays have a delayed release formula, which allow the herbicide to stay in the grass long enough to kill the crabgrass and any weeds that may be growing around the base of the grass. Other formulations allow the herbicides to stay in the grass, but provide protection for the grass from wind and sun.