6 Points to Keep in Mind When Making a Crabgrass Pre-Emergent Application

As we all know, timing is crucial for crabgrass pre-emergent applications. We all try to apply our pre-emergent as close to the germination window as possible. In North Eastern Ohio, this can vary year to year and is strictly based on soil temperatures. Generally speaking, the 1st week of May is when we start to see crabgrass germinating in high cut turf areas. Besides timing, there are additional factors that will increase your overall success.

Some other points to keep in mind:

• Make sure to calibrate your application equipment and keep track of your product usage at least daily. This will help you catch any changes in material use and correct them before it’s too late.
• Border all edges of properties abutting concrete, brick, or asphalt. These are always problematic crabgrass areas.
• Consider split applications.  This will help extend your control into the summer when you need it most.
• Do not try to “stretch” a higher active ingredient material to cover more areas.  This only results in less than adequate particle distribution and will lead to poor performance.
• Hit your target AI/Acre. In Northeast Ohio, that would be a minimum of .25 lbs. AI/Acre for Dimension, or .65 lbs. AI/Acre for Prodiamine.
• Apply 21-22-4 starter fertilizer with Mesotrione when seeding in the spring-summer months. This will help prevent weeds from impeding the new grass from establishing. Cool-season grasses will always lose when competing with the crabgrass or other annual grasses in the summer.
• An overlooked factor is the influence prill size has on efficacy. Applying a 4 lbs./ 1000 sq. ft. rate of material with an SGN of 215 will provide 46% more particles per square foot than using a material with a 240 SGN.  Using a smaller prill size will not only apply a more consistent barrier, but it will also help lengthen your pre-emergent’s residual control.

Annual grasses are rarely prevented 100% of the time.  But, if you follow these guidelines, it will put you in a better position for success.