When is the best time to apply pre-emergent?

The secret to preventing and treating weeds is timing. Pre-emergents must be put down before crabgrass starts germinating to be effective. According to Purdue University, crabgrass starts germinating when the soil temperatures reach about 60 degrees Fahrenheit for at least 3 to 5 days. This generally occurs around mid to late April in central Indiana. Therefore, during March and April, we recommend that you apply a pre-emergent herbicide that blankets the soil, just in time to prevent grassy weeds like crabgrass and foxtail from germinating.

How does it work?

It is a common misconception that pre-emergents stop crabgrass from germinating. In fact, pre-emergent herbicides are designed to inhibit the growth after the germination has already started to prevent the plant from becoming established and emerging from the ground. Depending on which chemical makeup is used, pre-emergent herbicides work in one or more of three ways. By inhibiting root growth, inhibiting cell division, and/or inhibiting growth enzymes. The pre-emergent creates a chemical barrier that blocks plant growth and can last about 12 weeks without harming what is already there.

How do I apply pre-emergent?

There are many different pre-emergent herbicides on the market. They can come in either a granular or liquid form.

The following are general instructions to properly apply granular and liquid pre-emergents. However, it is important that you follow the manufacturer’s instructions.

Using a granular pre-emergent herbicide:

  • Pour granular pre-emergent herbicide into a spreader.
  • Apply the granules evenly at the manufactures recommended rate.
  • Follow-up with at least a half-inch of water within 14 days.

Using a liquid pre-emergent herbicide:

  • Pour liquid pre-emergent into a sprayer.
  • Spray evenly at the manufactures recommended rate.
  • Follow-up with at least a half-inch of water.

What to avoid:

  • Applying to newly-overseeded turf. You should wait at least 60 days after overseeding before applying pre-emergent or after the second mow.
  • Aerating turf too soon after application. While treating your lawn with pre-emergent, do not aerate or thatch. This will break the barrier and allow breakthrough
  • Not watering after application. Water is required after pre-emergent herbicide application to move the product below the ground’s surface to the area of seed germination.

Let us do it for you! At Lawn Pride, our pre-emergent herbicide is formulated for your Indianapolis lawn. Within the 7-Application Program, our pre-emergent and weed control treatment is combined with other essential treatments to provide the most effective solution for a healthy lawn. Our experts know when the timing, weather, and overall growing conditions are suitable to apply the pre-emergent.

With warmer weather on its way, don’t wait to be proactive. Contact your local lawn pros at 317-251-6800 to sign up for your 7-Application Program today!