Baking soda is a good solution for killing weeds in certain cases. This common household product will kill all small types of weeds. You can also use it to control powdery mildew, a fungal disease that affects beloved landscape plants such as rose bushes and lilac shrubs.
Baking soda weed killer is easy to use, whether you are applying it straight out of the box or preparing a solution with it to spray on the targeted weeds.
Learn why baking soda works as a weed killer, how to use it, and what its limitations are.
Weeds are the bane of many gardeners’ existence. They pop up uninvited in our flower beds, vegetable gardens, and pathways, stealing water, nutrients and sunlight from our precious plants. Getting rid of these pesky intruders often requires the use of harsh chemical herbicides that can be toxic to people, pets and beneficial insects. However, there are safe, natural alternatives for keeping weeds at bay without exposing your family and the environment to dangerous toxins. One such option is using a homemade weed killing spray made from two common kitchen ingredients – vinegar and baking soda.
Why Vinegar and Baking Soda Work On Weeds
Both vinegar and baking soda have properties that make them effective at killing weeds when used individually. Combining them creates a “one-two punch” that decimates weeds while still being safe for people and the planet.
Vinegar contains acetic acid, which gives it a low pH and allows it to burn and dry out plant tissues on contact. Acetic acid dissolves the waxy cuticle on weed leaves, allowing the vinegar to penetrate into the plant’s tissues and kill it. White distilled vinegar typically contains 5-8% acetic acid, while horticultural vinegar may have up to 20% for enhanced herbicidal effects.
Baking soda, also known as sodium bicarbonate, has a high salt content. When absorbed by plant roots, the salt accumulates in tissues, dehydrating the plant and eventually causing death. Baking soda also raises the pH level of soil, making it more alkaline and inhospitable to acid-loving weeds.
Using vinegar and baking soda together combines these two mechanisms of action for more complete and effective weed control. The vinegar rapidly burns leaves while the baking soda kills roots and sterilizes soil to prevent regrowth.
How To Make And Apply A Vinegar-Baking Soda Weed Spray
Making a vinegar and baking soda weed killing spray right at home is quick, easy, and inexpensive. All you need are three common household items:
- White vinegar
- Baking soda
- Liquid dish soap (optional)
Step 1 Combine 1 part baking soda with 2 parts vinegar in a spray bottle or tank sprayer. For example for a 24 oz spray bottle use 8 oz baking soda and 16 oz vinegar.
Step 2 The mixture will immediately begin bubbling and fizzing as the acetic acid in the vinegar reacts with the sodium bicarbonate in the baking soda. Once the reaction subsides, shake the bottle to dissolve any remaining baking soda.
Step 3 (optional): Add several drops of liquid dish soap and shake again. The soap helps the spray stick to weed leaves rather than beading up and rolling off.
Step 4: Spray weeds thoroughly on a sunny, calm day, coating all leaves and stems. For best results, spray in the morning or early afternoon when sunshine will enhance drying. Avoid windy conditions that may blow the spray onto desired plants.
Step 5: Discard any unused spray mixture down the drain. Rinse the spray bottle thoroughly before reusing. The mixture loses effectiveness after a few days.
Tips for Using Vinegar and Baking Soda Weed Killer
Here are some helpful tips and precautions for getting the best results from your homemade vinegar and baking soda weed spray:
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Focus on young, actively growing weeds that will readily absorb the spray. Avoid mature weeds with thick, woody stems.
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Perennial weeds and deeply rooted plants may require repeat applications to fully kill the weed down to the roots. Spray any regrowth.
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Avoid spraying on windy days when spray drift could damage other plants. Use a shield to protect non-target vegetation.
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Wear gloves, long sleeves, pants, and eye protection when spraying to prevent skin and eye irritation. Avoid breathing fumes.
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Rinse off any spray landing on hard surfaces like patios, as vinegar can etch concrete. Avoid using near painted or metal surfaces.
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Sweep up any baking soda residue to avoid damaging grass or surrounding plants.
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Do not pour leftover spray down drains or into soil. Vinegar can kill beneficial soil microbes, while baking soda leaves salt residues.
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Test on a small area first to ensure the spray concentration is safe for your plants. Adjust vinegar strength if needed.
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Expect treated areas to be bare soil. Wait 2 weeks before replanting to allow residues to dissipate. Water well first.
When and Where To Use This Natural Weed Killer
A vinegar and baking soda spray works best on young annual weeds growing in cracks, beds, and areas where no desirable vegetation is present. Good uses include:
- Spot-treating weeds sprouting in patios, sidewalks, gravel paths and driveways
- Cleaning weeds from brick walls and fence lines
- Managing weeds in ornamental beds before mulching or planting
- Temporary vegetation control under decks, sheds, swing sets, etc.
- Large area weed control before planting landscaping or food plots
Avoid using near sensitive plants or lawns, as the salt residues may leach and damage nearby vegetation. Test on ornamentals first before widespread use. Hand-pulling is still the safest approach around valued plants.
Repeat applications will likely be needed on persistent perennial weeds with extensive root systems. For best results, apply to newly emerging growth and deplete the weed’s energy reserves.
Why Use A Vinegar and Baking Soda Weed Spray?
Reaching for a bottle of vinegar and box of baking soda to make your own natural weed killer offers many advantages:
Kills weeds effectively: The combined herbicidal effects of vinegar and baking soda provide rapid burndown and root kill for complete control.
Fast and easy to mix: Making a single batch takes just a minute or two with common household items.
Very inexpensive: Vinegar and baking soda are budget-friendly options you probably already have at home.
Non-toxic and safe: The ingredients pose little risk to people, pets, beneficial insects, birds, wildlife, aquatic life, or the overall environment.
Prevents chemical hazards: Avoid exposing your family to dangerous glyphosate, 2,4-D or other toxic herbicides.
Readily available: Purchase ingredients at any grocery store without licenses or permits required for commercial herbicides.
Works quickly: Weeds begin wilting within hours, with full effects visible in 1-2 days.
Satisfying to use: Mix up a batch and take out your weed frustrations with a squirt bottle!
FAQs About Vinegar and Baking Soda Weed Control
Q: How much vinegar and baking soda do I need per gallon of water?
A: A good starting ratio is 1 part baking soda to 2 parts vinegar, mixed into 1 gallon of water. Adjust the vinegar strength as needed.
Q: Can I use apple cider vinegar instead of white vinegar?
A: Yes, apple cider vinegar will work but may require higher proportions for the same effect on weeds. Always test concentrations first.
Q: How long does it take for weeds to die after spraying with vinegar and baking soda?
A: Most young weeds will begin showing signs of damage within 3-6 hours. Larger or deeply-rooted weeds may take up to 3-5 days to fully dry out and die.
Q: Should I add dish soap to my vinegar and baking soda weed spray?
A: A small amount of dish soap helps the spray solution stick to weed leaves rather than beading up. But it is not mandatory.
Q: Is it safe for my kids and pets to enter treated areas?
A: Yes, vinegar and baking soda residues are non-toxic once sprayed and dried onto plants. Just keep children and pets away during application until spray dries.
Conclusion
If you are seeking an effective yet non-toxic weed control option for your home landscape, making your own vinegar and baking soda spray is a smart choice. Combining the burning power of acetic acid and the dehydrating salt action of sodium bicarbonate provides a knock-out punch to weeds without harming your family or environment. Mix up a batch using supplies you likely already have in your pantry and say goodbye to pesky weeds!
Why Baking Soda Works on Weeds
The reason baking soda is effective in killing weeds is that one of its major ingredients is salt. In sufficient quantities, salts effect on plants is to dehydrate them.
If you want to kill a weed permanently, this is one way to do it: dry it out so much that it cant take up water anymore, and the weed will die for good.
Although it takes a higher dosage of baking soda to kill a larger plant (such as a shrub), its still advisable to apply baking soda cautiously to shrub foliage when using it to control powdery mildew. When mixing your solution, use one tablespoon of baking soda per 1 cup of water.
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Where to Use Baking Soda
Baking soda is a non-selective herbicide, so unfortunately it could kill small plants and grass. Use it on isolated weeds, like in between pavers, along the edge of the driveway, or in sidewalk cracks.