Pre-Emergent Application?

When Should You Apply Pre-Emergent?

By the time you see crabgrass, it’s already too late.

One of the biggest mistakes homeowners make each spring is waiting until weeds appear before taking action. Pre-emergent herbicide doesn’t kill existing weeds — it prevents them from ever sprouting.

Timing is everything.

What Is Pre-Emergent?

Pre-emergent is a preventative herbicide designed to stop weed seeds, like crabgrass, from germinating. It creates a barrier in the soil that disrupts root formation as seeds begin to sprout.

But here’s the key:

It must be applied before germination starts.

The Right Timing in Central Oklahoma

In Cushing and surrounding areas, pre-emergent timing is based on soil temperature - not air temperature, and not calendar date.

Target Soil Temperature:

55°F at a 2-inch depth for several consecutive days

That’s when crabgrass begins to germinate.

In most years around central Oklahoma, this occurs:

• Late February to early March (early warm springs)

• Mid-March (most common window)

If you wait until late March or April, you risk being behind the cycle.

Why Soil Temperature Matters

A few warm 70° days in February can fool homeowners into thinking it’s time to act — or worse, delay action.

Weed seeds respond to consistent soil warmth.

Air temperatures fluctuate wildly in Oklahoma. Soil temperatures rise more steadily.

Professional lawn management monitors soil conditions, not just how it “feels” outside.

Common Pre-Emergent Mistakes

Many lawns fail to control weeds because of:

• Applying too late
• Not watering it in properly (½ inch irrigation required for activation)
• Disturbing the soil barrier with heavy aeration
• Using the wrong product for turf type
• Overseeding after application (which pre-emergent will prevent)

Prevention requires proper sequence.

Bermuda vs. Fescue Considerations

For Bermuda:

• Early application before consistent 55° soil temperatures is ideal.

• A second split application can extend protection into summer.

For Fescue:

• Timing is similar, but you must consider fall overseeding plans.

• Spring pre-emergent will prevent new grass seed from germinating.

The Difference Between Prevention and Reaction

Weed control is reactive.

Pre-emergent is strategic.

The best lawns are built on prevention, not correction.

If you want a thicker, more uniform lawn heading into Oklahoma’s summer heat, proper early-season planning is critical.

Timing matters.

— Cardinal Outdoor Services
Serving Cushing, Stillwater, Perkins, and surrounding communities with strategic lawn management.