Vinegar - An Organic Herbicide

Acetic Acid. Long known for it's ability to kill weeds (vegetation), is recommended as an organic treatment which does its work, then dissipates with rain or watering-in. Although it can acidify surface dirt if you pour it on the ground, it is not recommended as an acidifier of planting dirt. Vinegar spray quickly dissapates with light watering the next day and is not considered detrimental to earthworms or microbe populations in the ground, but don't use it on or around a compost pile.

5% household vinegar is NOT the product of choice. 20% vinegar (or stronger) will do the job, but for tough weeds may take more than one application. Industrial acetic acid over 30% is NOT recommended, and care should be taken not to get any acid of any kind on skin, and especially avoid possiblity of spray or splatter in eyes.

Overspray can be a consideration for tender vegetable plants, but is not nearly the concern that using glyphosate or some other artificial weed killer would be, since a flushing of water the next day will clear any effective residue, and does not get taken down into roots.

In this page a number of links are listed with a short note - for perusal at your leisure. This author has tested many variations of these vinegar remedies and found them all to work to varying degrees, depending on which plants were being eradicated. I have favorite recipes for weeds where I live, but don't share them, since each is specific to my location and do change the recipe, based on the kind of airborne weeds that our location has, at different times of the year.

As an organic gardener, to the degree you are able to identify the common weeds in your area (the ones you desire to eradicate), at different seasons, you can learn to target them with a particular concoction of your own making - with only a few ingredients easily mixed in a hand or pump-up sprayer, depending on the size of area to be treated. And there are some rather ingenious devices to control over-spray.

The government study links provide scientific research validation, on which the rest 'coat-tail'. Although vinegar was used and accepted by homeowners LONG before the USDA got around to validating the product - as usual.

http://www.ars.usda.gov/is/pr/2002/020515.htm Agricultural Research Service scientists offer evidence that vinegar may be a potent weedkiller that is inexpensive and environmentally safe. ______________________________

no mention of the quantity of orange oil or canola oil used, but from other information, one tablespoon per quart of either or each, is the common dosage.

INSTEAD of using one or more oils as a spreader in the acetic acid, some folks prefer one drop of a liquid detergent per quart of vinegar as a surfactant (wetting agent) although a greater amount may be used - but suds is not a recommended method of treatment, and use of a soap product to cut oil - and use of an oil as a spreading agent would be counter-productive. This author's favorite detergent as a wetting agent is Ivory liquid.

Do not use vinegar on/around compost piles, as vinegar has shown to have potent microcide properties. Some nurseries and garden stores now stock (or can order) 30% vinegar. Use with protective equipment and caution around all vegetable plants. ______________________________

Below is another government study, accepted by ARS/USDA: http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=176567 Oklahoma Agriculture Experiment Station Departmental Publication - January 31, 2005 ______________________________

Next is a CYA effort by the Oregon Dept. of Agricultural - but provides some noteworthy points worth reading by all. http://oregonstate.edu/dept/nursery-weeds/weedspeciespage/acetic_acid_factsheet.pdf ______________________________

Next is a weigh-in by the Wisconsin Master Gardener Association (Extension Service) that basically says the same thing - that anyone making lists of 11%+ vinegar OUTLETS is tantamount to directing people to use an unregistered pesticide. So no lists of where you can purchase PICKLING vinegar are made by this author. http://www.hort.wisc.edu/mastergardener/features/weeds/vinegar/vinegar.htm ______________________________

OK, now that we have official government findings on which to substantiate (or not substantiate) use of vinegar as a weed killer, let's investigate the kind of "concoctions" that some folks have come up with, along with advice for using it:

I like the way this site puts the information for home use. http://gardening.about.com/od/naturalorganiccontrol/qt/Vineger_Herbici.htm

Some trial-and-error advice, but not clear on what strength of vinegar was used. I think it was just 5% household vinegar - not very effective. http://www.garden-counselor-lawn-care.com/vinegar-weed-killer.html

A couple of 'twists' in this one, but not particularly helpful otherwise... http://landscaping.about.com/od/weedsdiseases/qt/vinegar_weeds.htm

A few more 'twists' - but some of these acids can be dangerous, and this author knows that bleach kills microbes and salt is not good for dirt. http://www.small-farm-permaculture-and-sustainable-living.com/organic_weed_killer_formula.html

This one gives more recipes - but again, using just 5% household vinegar will probably require repeated applications... http://www.buzzle.com/articles/vinegar-weed-killer-recipe.html

Well, this could go on and on - which you can do on your own if that's what you'd like to do. The purpose of this page is to provide an opportunity for readers of this site to get some basic information. This author still suggests that hands-and-knee activity is valid to keep weeds at bay - and heavy mulching with grass clippings or hay is my favorite technique to keep weeds down in the first place, and I don't have ANY 'lawn' per se, but when weeds need some "extra zapping"...