Crabgrass is a problematic lawn weed that tends to intrude even to the well-maintained St Augustine grass. It is a pesky bad weed that is aesthetically unappealing and can significantly damage your lawn. The weed takes away essential nutrients from your grass, making your property look terrible. In this article, you’ll learn how to naturally and chemically kill crabgrass in St Augustine grass. Read on.

You can eliminate crabgrass in St Augustine grass chemically by applying herbicides or naturally by using boiling water and vinegar. Other great ways of getting rid of crabgrass in your lawn are by burning the weeds and applying baking soda. However, the best defense against this weed is to keep your St Augustine lawn healthy and well-watered.

How to Kill Crabgrass in St Augustine Grass

How do you kill crabgrass in St Augustine grass? This question bothers many gardeners and homeowners with this pesky weed in their St Augustine lawns. You can effectively use any of the following methods:

1. Use boiling water

One of the simplest ways to kill isolated patches of crabgrass in your St Augustine is by applying boiling water. Soak all affected areas with boiling water several times to eliminate the weeds effectively. However, be careful when using this method, as the water may also kill the grass.

2. Apply herbicides

The best way to kill crabgrass in any lawn is by applying herbicides. However, you’ll not get an herbicide that will kill active crabgrass and is also safe for St Augustine.

Use Celsius with a Surfactant (pictured below), Agralawn Crabgrass Killer, or RoundUp, as they have a minimal reaction to your lawn. You can also use glyphosate or glufosinate for spot treatment.

3. Use vinegar

Another simple organic way to eliminate crabgrass is by spraying the affected area with apple cedar or white vinegar. The method is more effective if you apply the product multiple times during the hottest days. The product makes the crabgrass to wilt and die.

4. Apply baking soda

Another suggestion for killing crabgrass in St Augustine grass is by applying baking soda to the affected areas. The sodium in the product will make the weeds wither and die after multiple applications. However, you must be careful during the application as the product can damage your grass if you overshoot.

5. Burn the weeds

Using a weed burner, heat gun, or blow torch, you can also burn crabgrass to eliminate it from your St Augustine lawn. This method exposes crabgrass and other weeds to extreme heat that damages the cells in the stems and leaves. The weeds die instantly as they will stop manufacturing food.

Killing Crabgrass in St Augustine FAQs

Q: What causes crabgrass in St Augustine grass?

A: Your St Augustine grass could have crabgrass if the turf is thinning or the yard receives excessive sunlight. The weed also thrives in areas with sandy and compacted soil.

Q: How do you prevent crabgrass in St Augustine lawn?

A: The best way to prevent crabgrass from taking over your St Augustine lawn is by mowing to the appropriate height. If you cut the grass too short, crabgrass will germinate in your property’s thin and bare patches. Also, remember to regularly water, fertilize, dethatch, and aerate your yard to prevent these weeds from sprouting.

Final Thoughts

So now, how do you kill crabgrass in St Augustine grass? Crabgrass is a troublesome broadleaf weed that can quickly ruin and take over your St Augustine lawn. But the good news is that you can get rid of it in several ways using chemical and natural treatments.

If you need to know how to kill crabgrass in St Augustine grass, here are the ways: Apply herbicides, baking soda, vinegar, boiling water, or burn the weeds.