How to Stop an Armyworm Invasion: Natural and Synthetic Lawn Treatments
If you have noticed large patches of your lawn turning brown almost overnight, you might be facing a full-blown armyworm invasion. Fall armyworms are notoriously destructive and can strip a lawn down to the dirt in a matter of days. When these pests march into your yard, you have to act fast.
In my latest video, I walk you through the most effective ways to kill armyworms and stop them from destroying your grass. Whether you prefer a fast-acting synthetic approach or a natural, biological method, here is exactly how to handle the problem and help your lawn recover.
Armyworm Lawn Treatment Video
Products Used
UTV / ATV Tank Sprayer → HERE
Double Kill Granular → HERE
Spinosad → HERE
Hose End Spray → HERE
Method 1: The Synthetic Approach for Fast Knockdown
When you have a severe infestation and need immediate results, a two-step synthetic treatment is highly effective. The goal here is a quick knockdown of active caterpillars and a residual barrier to prevent more from hatching.
- The Granular Base: I start by applying The Andersons Duocide. This is an excellent granular insecticide that provides a strong residual barrier in the soil and turf canopy.
- The Liquid Knockdown: After laying down the granules, I follow up with a hose-end spray bottle of either Spectracide or Triazicide. Spraying this directly over the lawn provides an instant contact kill for the armyworms actively feeding on the grass blades, while also watering in the granular Duocide.
Method 2: The Natural and Organic Approach
If you prefer not to use synthetic chemicals on your lawn, you can absolutely control armyworms using natural, biological treatments. These methods specifically target caterpillars and worms without harming beneficial insects like bees and ladybugs.
- BT (Bacillus thuringiensis): BT is a naturally occurring soil bacterium that is toxic to caterpillars. When armyworms consume grass treated with BT, it paralyzes their digestive system, and they stop feeding immediately.
- Spinosad: Another fantastic organic option, Spinosad is created through the fermentation of a naturally occurring soil bacterium. It works on contact and through ingestion, making it a highly effective natural insecticide for lawn pests.
Lawn Recovery: Bringing Your Grass Back to Life
Killing the armyworms is only the first half of the battle. Once the pests are dead, your lawn needs immediate nutritional support to repair the damage and push new growth.
To jumpstart the recovery process, I apply Lawn Alive. This product is fantastic because it contains beneficial mycorrhizal fungi, which attach to the grass roots and drastically improve the plant’s ability to absorb water and nutrients from the soil.
Finally, I hit the lawn with a heavy dose of liquid fish fertilizer. I will warn you right now: this stuff absolutely stinks! However, the smell is worth it. Fish fertilizer is packed with easily accessible nitrogen and vital nutrients that will help your grass green up and heal quickly from the chewing damage.
Watch the Full Video
For a complete visual walkthrough on how to apply these products correctly, be sure to check out the accompanying video. Taking action at the first sign of armyworms is the key to saving your lawn.
