Looking for a homemade crabgrass killer? Having tested quite a few options, baking soda came out on top as the best way to kill crabgrass naturally. After applying the remedy, the weed starts to die within a few hours.
To kill crabgrass with baking soda, wet the patch of weeds lightly and then sprinkle baking soda generously over the foliage. Leave the powder for 1-2 days to desiccate and kill crabgrass before patching up the lawn. This DIY remedy works best on a hot, sunny day.
Baking soda (sodium bicarbonate) works by extracting water from foliage, stems and roots. Excess water loss causes cell and tissue destruction, making weeds like crabgrass to die quickly.
Does baking soda kill crabgrass permanently?
Yes, baking soda desiccates and kills crabgrass permanently and it works best because crabgrass does not have underground rhizomes that can sprout back after the foliage is destroyed.
To kill crabgrass permanently with this homemade solution, target young and actively-growing crabgrass plants. Weeds that are yet to go to seed are easier to control because there’ll be no crabgrass seeds to germinate in the spring.
How to Get rid of Crabgrass with Baking Soda
A single application of baking soda can get rid of young crabgrass but you may need 2-3 applications to kill the weed permanently. Being a contact herbicide, this DIY fix acts fast with results starting to show within hours. But how do you use baking soda to kill crabgrass?
1. Wet the patch of crabgrass you want to kill
Lightly sprinkle the patch of crabgrass with water. This will make it easy for the sodium bicarbonate powder to stick to the foliage and stems for maximum contact effect.
If you’re treating the lawn weeds in the morning, there may be dew on the grass. In such a case, you don’t need to water the turf to make it wet. Instead, go straight to the next step.
2. Cover neighboring grass and plants
Since baking soda is a nonselective natural weed killer, it will cause injury to any plants it comes into contact with.
To get rid of crabgrass without killing turfgrass, cover the grass neighboring the patch of crabgrass with a cardboard or other safe material to prevent contact with baking soda.
Did you know: Tenacity Turf Herbicide kills crabgrass without killing grass?
3. Sprinkle baking soda on the crabgrass
The next step is to sprinkle baking soda on the patch of wet crabgrass. Make sure to cover the foliage adequately because this homemade crabgrass killer works as a contact herbicide.
You might want to repeat this step if, after a few days, there are still a few instances of crabgrass in your lawn or garden. Watering the powder in can also help get rid of weeds with underground runners such as quackgrass.
4. Leave the weed to die off completely
After sprinkling crabgrass with sodium bicarbonate powder, the weed’s foliage will start appear white because of the paste. Watch out for the following signs that crabgrass is dying:
- Wilting foliage
- Leaf discoloration – leaves will start turning brown or black
- Stunted growth
These are signs that the baking soda weed killer is working and that the crabgrass is dying. Allow enough time for the weed to die off completely before going to the next step.
5. Uproot the dead crabgrass
For complete destruction of crabgrass, make sure to pull the weed by hand to clear the area for reseeding with turfgrass. You can also use a crabgrass weed puller such as the Fiskars Stand-Up Weeder to make your work a lot easier.
But why is this step important in the crabgrass control plan?
Crabgrass and other aggressive lawn weeds like to grow in areas that are thin or bare. So, you’ll need to pull up the dead crabgrass weeds in preparation for patching up the bare spots – which is the next step in this procedure.
6. Fill in the bare spots in your lawn
After uprooting the dead crabgrass, there will be bare spots in the lawn. Some weed removers can also leave the lawn with holes that need to be filled up and amended.
To fill in the bare spots with new grass, do the following:
- Prefill the holes where you removed crabgrass
- Spread topsoil over the bare patch.
- Spread grass seed and rake it in lightly.
- Apply a starter lawn fertilizer.
- Water the area lightly over the next few weeks.
Reseeding is an important practice for controlling crabgrass. It’s a great way to make your lawn grow full and thick and able to choke out weeds like crabgrass so you won’t have to use chemical or homemade crabgrass killers.
Here’s a video guide for the process:
You can increase the potency of baking soda by mixing baking soda with vinegar if you intend to create a more permanent weed control solution for crabgrass, quackgrass, and dallisgrass.
Caution: Crabgrass will kill every plant it comes into contact with because it is a non-selective homemade weed killer. To prevent injury to desired plants and turfgrass, it is best to treat large patches of crabgrass with bicarbonate soda as opposed to small infestations dotted all over the lawn.
Other Homemade Crabgrass Killer Recipes
Baking soda is great on its own as a weed killer, but you can make it even better as an ingredient in other homemade crabgrass killer recipes. Vinegar and cinnamon are my best go-to ingredients to pair with sodium bicarbonate to kill crabgrass.
Baking soda + Cinnamon Recipe
Cinnamon is present in some natural weed killers such as Agralawn Crabgrass Killer and has proven to be an effective herbicide for killing crabgrass permanently.
When mixed with baking soda, cinnamon oil makes the herbicide even more powerful at getting rid of crabgrass for good.
Here’s the homemade recipe for crabgrass:
- Add half (½) a cup of baking soda to a gallon of water.
- Add a teaspoon of cinnamon bark extract or oil.
- Stir to mix these ingredients well.
- Spray the mixture on crabgrass.
When I tried this, crabgrass started to show signs of desiccation within 2 hours on a sunny day. By the end of 3 days, the weed was completely gone.
Baking soda + Vinegar Crabgrass Killer
Vinegar and baking soda recipes are also effective at killing crabgrass and other weeds permanently. Like bicarbonate soda, vinegar also desiccates weeds, forcing them to die permanently.
Mix one part of baking soda with two parts vinegar and spray the solution on crabgrass or other weeds in the lawn. Repeat the application until the weeds are removed permanently.
Vinegar is acidic and will burn the weeds in your lawn, killing them within a short time. When combined with baking soda, they make a great homemade crabgrass killer.
References + Resources
- University of Illinois Extension: Homemade herbicide considerations
- Doug Caldwell, University of Florida, Collier County Extension: Crabgrass Management is Difficult!
- Aimee Colf et al, North Caroline State University Extension: Organic Gardening