* BE EXTREMLY CAREFUL WHERE YOU USE IT, THIS WILL MAKE THE SOIL UNUSEABLE FOR A COUPLE MONTHS, AND THIS WILL KILL ANYTHING IT COMES IN CONTACT WITH *
1 gallon of white or distilled vinegar
1 cup of salt
2 tbsp liquid dish detergent unscented
1. Pour one gallon of vinegar into an all-purpose, outdoor sprayer, or any container of your choice.
2. Add one cup of salt. Morton Salt works nicely, but any brand of salt will also work great
3. Add two tablespoons of liquid dish detergent. Ivory liquid dish detergent, or any other detergent will work. However, try to stay away from the scented detergents.
4. Mix all ingredients together by stirring. If you have combined the ingredients in a lawn and garden sprayer, put the lid on securely and shake to mix.
5. Spray directly onto weeds or you can pour directly into the cracks of walkways and driveways where weeds are growing.
How each ingredient works.
Vinegar is distilled through a fermentation process from grain, apples, or grapes. Common household vinegar has an active ingredient called acetic acid, usually diluted to a 5% concentration. This may be labeled as 5% acidity.
Acetic acid, like most strong acids, is a desiccant. That means it removes moisture. When sprayed on plant foliage, the water in the leaves is drawn out, and the top growth of the plant is killed. Whether or not the root is killed depends on the type of plant and its maturity.
The strength of the solution of acetic acid determines how fast and how completely it will kill weeds. Full strength vinegar, not diluted with water, will be strongest. Vinegar with higher acidity is available, though it is not commonly found everywhere. A serious caution on using stronger vinegar in a home made weed killer formula, or for any household usage, will be presented later.
Vinegar is not selective when it is sprayed on plants. It has the potential to kill any and all foliage. This means that if you spray weeds in your lawn, your grass will die as easily as the weed. If you spray weeds in your flower bed or vegetable garden, the good can die as well as the bad. As a home made weed killer, vinegar will have limited application, and will require that valuable plants be protected.
Some plants may be more resistant to absorbing it. Leaves with a waxy or hairy covering may absorb less of the solution and suffer less damage. Some plants may die above ground, but send up new growth from the root. This means that you will not get 100% control using vinegar as a home made weed killer.
Many of the homemade weed killer recipes include salt. Most suggest regular table salt, some say water-softener salt, others mention rock salt. Salt is salt. Salt kills plants. It may be added to some recipes to kill the plants when vinegar alone won’t.
Salt also acts as a desiccant, drawing moisture out of the plant. Most recipes are intended for use as a foliar spray. A few will instruct you to drench the soil around the weeds, expecting to kill the root more successfully.
Salt is problematic. It will get rid of your weeds, but also anything else nearby. It will hang around, leaving you with long term difficulty when you want to grow desirable plants. You may have heard the term “burned a plant with fertilizer”. That is because regular fertilizer is a salt. Apply it too heavily and plants die. Salt can remain in the soil, even affecting roots from distant plants.
If your desire in wanting to use home made weed killer is because you want natural products, instead of chemicals, don’t use salt as a weed killer. It defeats the effort of trying to develop healthy soil.
The one exception might be if you are spot treating weeds that pop up in cracks in your driveway, patio or sidewalks. Just use it sparingly, as it can leach into the area where good plants live.
The soap added to these formulas for homemade weed killer is primarily to improve the absorption of the spray. Liquid dish detergent (not dishwasher or hand soap) is the most effective at this.
Soap is able to break down the cuticle or waxy surface found on many weeds. This makes the plant more susceptible to the action of the active ingredient, like the acetic acid. Soap also breaks the surface tension of water, which helps it to stick to the leaves, rather than running off. This allows more of the killing agent to hang on and get working.
Soap is usually an oil derivative. Oil kills plants. Some soaps might kill plants themselves if they were applied in a strong enough concentration. A sideline benefit of adding the soap is that it is easier to see where the spray goes. The weeds will look shiny, as if coated with oil. This helps keep track of the sprayed area.
These results provide good reason to add soap to a home made weed killer. The amount of soap required as an additive would be small, no more than 1 ounce per gallon. As a sole ingredient to kill weeds, the concentration would have to be much higher
* USE THIS AT YOUR OWN RISK. *