Step 4: Theory 4: Killing Weeds

Picture of Theory 4: Killing Weeds
Killing weeds comes up as another use of vinegar, so i decided to try it on some undesirables in my back yard.

RESULT: Adding a strong acid to a plant should kill it, but i won't know for a few days if it worked as well as i hoped.
baseballer3 years ago
vinegar is diluted acetic acid, HC2H3O2, which is a weak acid.  It does not dissociate completely in water, unlike a strong acid.  It may be in high enough concentration that the hydrogen ion concentration is high enough to do some damage, but vinegar is not a "strong acid."  but nice tutorial tho.
lday14 years ago
i put a bit of dishsoap in the vinegar as it helps keep the vinegar on the weeds instead of dripping off. Spraying at anytime has worked but it does happen a bit faster if you do it on a sunny day.
ruminant14 years ago
We have had good results killing weeds by spraying store-grade vinegar on their foliage. This method killed some sprouting pyracantha that even Roundup wouldn't touch. We tend to put the vinegar on on the morning and let the afternoon sun work on it. By the end of the day, the plant is a goner.
jijizworld4 years ago
what kind of salt?
from what i've read, vinegar is to be applied to the weeds in the morning. the sun must also shine that day to somewhat "fry" the weeds and don't get it on any plants that you don't want to die. I've never tried it tho so if anyone has any more insight i'd be happy to hear it!
MoeK4 years ago
To kill weeds use Horticultural Vinegar. It is at 20% concentration rather than 4%. Results are immediate. Don't use it on your french fries.
Wragie MoeK4 years ago
The strong stuff we get around here is 35%. I've used the household stuff warmed up and it works almost as well and a whole lot cheaper. Only bad part is strangely the whole yard smells like a French fry for a day or so.

The best thing about using vinegar verses salt is that unlike salt you have no risks of messing up the soil for a few years.
Nyxius Wragie4 years ago
on a side note: store grade vinegar is only 5% and is probably too weak to be practical. It would take several applications to be effective.
Nyxius Wragie4 years ago
By pouring vinegar on an area you are essentially creating salts of acetate. Salt kills plants by making the water they absorb more salty than the fluid in the cells (hyper-tonic solution). Osmosis sets in and the result is a plant soaked in water that is dying of dehydration. Same thing can happen in people if to much salt gets into the blood stream. On the other hand too little salt in the blood causes critical organ swelling.
Keely10014 years ago
The best way I've found to kill weeds is to pour boiling water on them. No salt needed. Can't get more eco-friendly than that.
trog-oz5 years ago
Salt is a more effective weed killer than vinegar. 1 pound of salt in 1 gallon of boiling water will keep your paths weed free.