Homemade Weed Killer

   Mix vinegar with a bit of liquid soap is quite the effective weed killer. The general ratio is one ounce of soap to one gallon of vinegar. If you’re mixing a smaller batch, adjust using less liquid soap.  Vinegar is made of acetic acid, which removes the moisture from the plant. The liquid soap helps the vinegar stick to the plant’s leaves. Most Vinegar is only 5% acidity which will work OK, but 10% or 20% acidity* is much better. You can check most garden supply stores for stronger acidity vinegar.
       For optimal results use the  solution on a hot, sunny, dry day. You’ll kill anything you spray, so be careful around the plants you want to keep. Vinegar weed killer will not kill the roots of plants only the foliage.  You might have to use repeat applications to kill the weeds. Compared to commercial weed killers this method is still cheaper to use.
       Finally, Some recipes have adding salt to the weed killer recipe. I have tried both methods and each works. I prefer just using vinegar without salt cause most of the time you can't plant anything in the spot for a while.

* A good friend has suggested to reduce the vinegar by 1/4 by boiling it on the stove. Most vinegar is reduced to 5% acidity by adding water to it per most labels on vinegar.