What Pre-Emergent Does

A pre-emergent prevents weed seeds from germinating.

It does not kill the existing plant. It stops the new root and first leaves of a germinating weed seed. That is why it is so important to get the pre-emergent into the soil, where it forms a barrier.

It won’t kill weeds you can already see. For those, see our post-emergent guides, like our Bermuda post-emergent guide.

Timing

Timing matters more than anything.

Apply before weed seeds germinate.

Simple rule: apply in the first of February, the first of May, and the first of September.

Even Coverage Matters

Apply it evenly across the whole lawn.

Smaller Particles Work Better

The smaller the particle, the better it works.

Granular vs. Liquid

Pre-emergent comes in granular and liquid forms.

Which one you use depends on the application tools you have. Homeowners typically use a granular product. Liquid is the other option.

With liquid, pros can cover more square feet per tank, but it must be watered in with as much water as possible. A pump-up sprayer doesn’t do a very good job unless you can water it in with your irrigation system or an extra hose.

Split Applications

Split applications extend how long you’re covered.

In the springtime, split applications are typically spaced 30 days apart.

Water It In

Pre-emergent has to be watered in after application.

Don’t Disturb the Soil Surface

Don’t disturb the soil surface after application.