why is this something that works? What is in aspirin that helps prevent plants from disease?

Many thanks for keeping us up to date with this, Nandina. I've been reading about this for some time now with great interest.

Keep us (and ME) posted! ;-)

Username...here is a little article to start your research.

Dorie (who misses her SC friend)

Here is a link that might be useful: A tidbit of information

Thanks for that link, Dorie.

Unfortunately the link refreshes my memory of a discussion a couple years ago. Aspirin doesn't contain salicylic acid rather it is acetylsalicylic acid.

Acetylsalicylic acid contains, at most, .1% salicylic acid.

I am no chemist and make no claims to knowing what I am talking about, so here is a link for research purposes: http://www.chemicalland21.com/lifescience/phar/ACETYLSALICYLIC%20ACID.htm

Long story short, my very vague and fuzzy recollection of the discussion from a couple years ago concluded that whatever benefit there might be in salicylic acid, it isn't to be found in aspirin.

Of course, I could be wrong and look forward to the educated, researched opinions of others on this topic.

First off... a hello to Dorie who is a real pro kind enough to post here at GW with 'real' answers to your questions. Of course, Dorie, I will keep you updated on my aspirin experiments.

I keep reading all the reasons why this aspirin foliar spray should not work. And yet, it does, especially on tomatoes, peppers and other veggies. The trick is to begin the treatment early in the growth cycle of a plant.

Hopefully some of you will experiment and report your observations. This is how we all learn. Thanks!

Today I have gone ahead and tried the asperin technique. (not with the Yucca...will buy some when I am shopping this week for next time)...thanks good info...Martha/zucchini

Hi Nandina. Thanks for doing this.

Rhizo 1, thanks for the link. I've been looking for that link for years. I judged a science fair project several years ago where salicylic acid was used and gibberilic acid was used. Both have been shown to stimulate different genes to protect the plant. What this kid did was use both SA and GA on the plant at the same time. When he did, a third gene (formerly dormant) was stimulated and the tobacco mosaic virus was completely eradicated. The plant went on to produce tomatoes with viable seeds. This science fair project was the best one I've ever seen in botany in 20 years of judging. He went on to take second place internationally. He also went on to score perfect 1600s on the SAT, twice. This kid was good!

So what might be happening is the aspirin might be stimulating more than one gene simply because it is not pure salicylic acid. Or the addition of the yucca extract could be helping in the same way the GA helped.

Hi Nadina,

In regards to this comment of yours :"I keep reading all the reasons why this aspirin foliar spray should not work. And yet, it does..."

First, please understand I am not telling you something doesn't work. I have no practical experience with what you are doing. I simply read the link that says salicylic acid does this and that. I then look at aspirin and find it isn't salicylic acid so wonder how it can be that acid that affects plants positively.

Perhaps .1% of the acid is enough, perhaps there is something else going on, I don't know.

I am curious to see some study results if there are any. Does anyone have any links to university studies with aspirin?

I am not saying a backyard experiment means nothing, but disease suppression is really hard to test for other than on a large scale.

Also, what is the purpose of the yucca?

While I am a skeptic by nature, I am not ruling anything out, I just want to understand the hows and whys. I have too many experiments waiting to be done and not enough diseases to test them on ;-)

I am not saying a backyard experiment means nothing, but...

Unfortunately much of what we know today about organic gardening has been the result of observers like Nandina. The academics call it anecdotes to mean that there was no Ph.D. dissertation done on the topic. Experiential evidence, in my book, is going to be very important. You can go to any university in the country and ask them if corn meal will kill disease in the soil and they will all tell you it does not. If you come to me, I can tell you that it killed every disease I have ever had in my turf when nothing else worked. I have spread that word and just about monthly I will read about someone else who is happy with the results of ordinary corn meal. I should also say that I've never had red thread or rust. These diseases are resistant to corn meal - that is taken from more experiential evidence. The successful use of beneficial nematodes to control grubs in the south (but not in the north) and the successful use of milky spore to control grubs in the north (but not in the south) is also based on people's experience, not universities. It is forums like these where that info is passed around and tested.

username,
I have been trying to find a few minutes to discuss your question. Do you remember the days when the motto of universities was "publish or perish"? Now the university motto is...'patent or perish'. Agricultural researchers cannot patent aspirin, cornmeal, willow water, compost teas plus the many other organic methods we use in our gardens today. All these useful techniques, many of which work better than patented, commercial products began in someone's backyard, barnyard or back-forty. Word of mouth, trial and error have tested these ideas through the centuries.

I consider GardenWeb to be the best backyard testing ground in the country for new organic ideas. Gardeners living in 50 states will take note of an experimental suggestion, try it and report results within these multiple threads. This is exciting and why I hope the owners of GW do not mess it up so badly that we a driven from the site.

So, username, be patient with those of us who tinker in the horticultural world. It may take us awhile to figure out why something works. The challenge is finding new organic methods to combat the ever increasing imported diseases and insects that are overwhelming this country.

nandina, thank you for the recipe!!!
I had found reference to Yucca being an excellent Grape Black Rot 'fungicide'... long story short, had really good results using your recipe. Super easy, inexpensive, and nice to spray a substance that cant hurt you.
Funny thing, after reading your recipe, I found a Yucca root at the store, put it on the scale and it weighed exactly 1 and a half pounds.
The solution filled 2 trays, 6 gallons worth, we used it 4 times (should have started earlier but it still helped a lot!), so I can still play with it on other plants this year.

Nandina,

What size aspirin tablets are you using (how many mg)? Do you think freshly made yucca extract such as you suggest making has any advantage over purchased extract other than lower cost? Are the effects of aspirin spray similar to those you get from using Messenger--improved vigor/flowering, etc. in addition to the disease resistance? Has anyone reported any phytotoxicity to any species?

Was spending a few minutes cruising through the Forums and this subject appeared again. So...here's an update on the 'aspirin technique'.

First, let me answer Ellen's questions. I am using one 81 mg. non-coated, chewable baby aspirin tablet to a gallon of water. The best type of yucca (with no added alchol) to use is the commercial form sold by herbal companies. However, I have also found that the edible yucca root sold in grocery stores also works well although it is not as 'soapy'. Barb in OH reports success using it as have many others. It is cheaper to use. To date I have had no problems with phytotoxicity nor have any been reported to me. Growing conditions vary all over the country. I can say that the aspirin technique does increase disease resistance and this encourages better growth and blooming.

Never content I have been experimenting with a new 'twist' to this idea. I planted a grouping of the low growing perennial Soapwort(Saponaria ocymoides)in a damp garden spot. This spreads quickly and the leaves also produce a soap. I trim off a packed cup of the top growth, add it to 3 cups of water, buzz this with my hand blender and let all sit on the counter for 24 hours. Then I strain it, restrain it through a coffee filter, pour in a gallon jug, fill jug with water, add one crushed 81 mg. aspirin tablet and when it dissolves, spray. I am very pleased with the results of this experiment, appears to be more effective than using yucca. It is possible to also use the tall growing form of Soapwort (Saponaria officinalis), but the low growing variety recovers quickly from being closely trimmed. Some of you may want to try this method and let us know your observations.

I have just recently got wind of the aspirin water for plants technique and I believe I have the article saved some of the above have mentioned and note the ratio as it is misquoted above.

The master gardener at the university of rhode island who was in charge of these tests has decided the best ratio is : 1.5 aspirin[81gr.] to two gallons of water and is best used after the aspirin have been crushed plus adding some liquid dish soap to make mix adhere to the plant surface. I will add the article.

I have added 1 aspirin to a gallon of water with some dish soap and sprayed my cuttings to see what effect it may have.

Here is a link that might be useful: aspirin water

As already mentioned, Asprin is "acetylsalicylic acid" not "salicylic acid". I'm surprised there has not been any discussion of applying the actual plant hormone, salicylic acid. There is a product out there made by Growth Products called "Recover Rx" which contains actual salicylic acid. Has anyone tried it? According to the product information, it contains .0625% salicylic acid. If I did the math correct, that would be .08 ounces of 100% salicylic acid per gallon of Recover RX. (.08 ounce = 2.4 ml)

I ordered "Salicylic Acid 20% Gel Peel" from amazon.com. It is a beauty product for facial skin peel. At 20% salicylic acid I would need to add 12ml (5 x 2.4ml) in one gallon of water to get the same concentration as the Recover Rx product. Hopefully the Salicylic Acid Gel Peel will mix properly in water. I might mix the salicylic acid into a cup of vinegar first before adding to water to avoid precipitate. I figure its worth a shot. Any thoughts or tips?

I know this post is rather old, but...

Acetylsalicylic acid is well known to degrade into salicylic acid and acetic acid in the presence of moisture, and even more so when dispersed in water. That plus the conditions of heat and light on the surface of plant leaves is sure the hydrolyze the aspirin to the active chemical you guys want (salicylic acid).

Thanks for sharing great idea on making your own yuca spray. However, the sellers of pure extract recommend not to freeze so maybe it sounds like 1 qt could be used in 1 season.