What is an effective all natural weed and grass killer?

Salt

Salt. Pour Morton table salt between cracks in sidewalks where weeds and grass come up. Pour enough that it is mounded up an inch or so above the sidewalk. You will be amazed!

Vinegar-the wonderful weed killer...

Vinegar. Or salt, but you can control your application better if you use vinegar. (unless you want to go through the trouble of mixing salt with water in a high concentration.)

Vinegar is great for many things and when it comes to weeds, it really works. Even on Ironweed, a tough cookie in our area. If you need to apply it to a weed or plant that's in the middle of other plants you don't wish to get a dose, then cut the top off of the weed or plant and dip in in the vinegar. This might take more than one treatment, of that I'm not sure. I've never done it that way. We always just pour or spray it over the area that needs treatment and a couple of days later your weeds are dying or already dead.

A Weed Killer formulation I've used for interlock brick, is to mix 1 gallon white vinegar, 1 cup table salt, and 1 tablespoon dishwashing liquid. I use 5% household vinigar with great success (my interlock has lots of very young, unestablished weeds). I'm told a 15%-20% strength is better but I can't seem to find it at a reasonable cost.

Other Ways

To my way of thinking, salt [sodium chloride] and vinegar [dilute acetic acid] are both chemicals! For a truly non-chemical method of spot killing any unwanted weeds or grasses is boiling water, or steam from one of those hand-held generators sold for cleaning. Using this technique, I have encountered only two problems.

First, if the amount and/or area of unwanted vegetation is large, it requires a lot of boiling and hauling of water. And second, if unwanted vegetation is in very close proximity to desirable plants, then great care is necessary to prevent contact of the boiling water or steam with the foliage or root system of those desirable plants which you do not want to harm.

Another method for killing relatively large areas, as for preparing for flower beds or garden plots, is to scalp mow the grass or weeds, then water well, and cover with a sheet of plastic. Stretch it as smoothly and tightly in contact with the mowed vegetation as possible, and well weighted down, especially around the edges to keep the water vapor contained.

The sun will generate heat which will be concentrated in the vegetation and soil, and water vapor which will develop over a relatively short time, will kill the vegetation. I think this method is called solarization.

Another natural method is, after scalp mowing, to simply bury the area which you want to clear of weeds with a six to twelve inch layer of any mulching material. This will kill everything, except the millions of seeds which exist in almost every cubic foot of ordinary soil.

IN ADDITION.

Don't use the boiling water method listed above. The state I live in tried a fire ant control system called steaming. It consisted of a stainless steel probe about 4 feet long with holes on 4 sides every 6 inches. They took this rod and inserted it into fire ant mounds and applied steam to kill all the ants. It did. Bad thing, it also killed all the bacteria in the soil as well and made it sterile for at least a year.

First answer by T George. Last edit by Hooweestik. Contributor trust: 753 [recommend contributor]. Question popularity: 45 [recommend question]