Citric acid foliar spray for powdery mildew?
- Thread starter goingrey
- Start date
OG_NoMan
Not Veteran
I have been using it as it's part of lost coast plant therapy but like you I would love to know a good source of just citric acid and the ratios to spray safely. Hopefully someone out there is doing this and will chime in because the lost coast is expensive and I am not trying to kill bugs outside so...
You can find dozens of pages on high PH water for controlling powdery mildew and that is what I use.
Potassium Bicarbonate 1 tablespoon per gallon of water apply as a drench spray once a week start to finish. A PH of 8 or higher is said to do it. My hose water is 8.5 and I still kick it up with bicarb into the 9s.
Household baking soda (sodium bicarbonate) will work too. 10 years I've used high PH water to keep PM in check.
goingrey
Well-known member
I'm no chemist but I would imagine adding an acid to water would lower the pH not raise it?
revegeta666
Well-known member
It would but the examples he gave you are products that make an alkaline solution and prevent spores to take root. I have never heard about acidic products to treat mildew, what we usually use here is bicarbonate, peroxide or just milk (all of them diluted)
Hasch
learning and laughing
From what I read (no personal experience) the milk should be "raw" as in untreated.
goingrey
Well-known member
I was googling some PM remedies and came across a product called Grower's Ally Fungicide and it is based on citric acid, so they say. And @OG_NoMan already mentioned Lost Coast Plant Therapy. It is not a novel idea clearly. Method of action must be different than with the alkaline drenches.
OG_NoMan
Not Veteran
Not to mention none of those products that revegeta666 listed have worked for me in the past when used. The lost coast is the first product I have used that actually works and works well.
revegeta666
Well-known member
Clearly not. I just said I never heard of acidic products to treat mildew, I wasn't saying they don't exist. Thank you for educating me once again @goingrey
goingrey
Well-known member
A paper on dill: (any ISHS members here with full text access?)
Effect of foliar application of three levels of citric acid (0, 0.1, and 0.3 % w/v) and three levels of malic acid (0, 0.1, and 0.3% w/v) on height, postharvest performance and yield indices (wet yield, dry yield and essential oil yield) of dill (Anethum graveolens) was studied. The experiment was conducted in a randomized design factorial arrangement (3×3), with four replications. Factorial analysis revealed that citric acid caused the incidence of powdery mildew to decrease significantly. Malic acid increased the plant height significantly. The combination of factors increased wet weight, dry weight, keeping quality characteristics of stored fresh dills and essential oil yield of dills comparing with control treatment. The possible mechanisms of action for these substances are discussed.
So this would be between 1-3 g/l?
About the alternative treatment and its effectiveness or lack thereof I hear there are already dozens of pages on. The mention was good but maybe we don't need to discuss it further in this thread.
GROWTH AND ESSENTIAL OIL YIELD OF DILL (ANETHUM GRAVEOLENS) AS AFFECTED BY FOLIAR SPRAYS OF CITRIC ACID AND MALIC ACID
ISHS I International Symposium on Medicinal, Aromatic and Nutraceutical Plants from Mountainous Areas (MAP-Mountain 2011) GROWTH AND ESSENTIAL OIL YIELD OF DILL (ANETHUM GRAVEOLENS) AS AFFECTED BY FOLIAR SPRAYS OF CITRIC ACID AND MALIC ACID
www.actahort.org
Effect of foliar application of three levels of citric acid (0, 0.1, and 0.3 % w/v) and three levels of malic acid (0, 0.1, and 0.3% w/v) on height, postharvest performance and yield indices (wet yield, dry yield and essential oil yield) of dill (Anethum graveolens) was studied. The experiment was conducted in a randomized design factorial arrangement (3×3), with four replications. Factorial analysis revealed that citric acid caused the incidence of powdery mildew to decrease significantly. Malic acid increased the plant height significantly. The combination of factors increased wet weight, dry weight, keeping quality characteristics of stored fresh dills and essential oil yield of dills comparing with control treatment. The possible mechanisms of action for these substances are discussed.
So this would be between 1-3 g/l?
About the alternative treatment and its effectiveness or lack thereof I hear there are already dozens of pages on. The mention was good but maybe we don't need to discuss it further in this thread.
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revegeta666
Well-known member
When you said this in your original post:
I thought you meant if there existed other methods, that's the only reason I mentioned those products. Literally just trying to help
but that's ok I bet there's something interesting on Netflix.
goingrey
Well-known member
Solution shelf life, when to apply and especially when not to, how often, preventative vs remedial.. this kind of considerations I had in mind.When you said this in your original post:
I thought you meant if there existed other methods, that's the only reason I mentioned those products. Literally just trying to help
OG_NoMan
Not Veteran
I am gonna test this this fall. I got some clones rooting/rooted so as soon as I can multiply them again into many plants I am gonna start the citric acid. I am interested to see if it just washes the pm off like the lost coast or if an oil and soap have to be added also. I might just try to recreate the lost coast as all the ingredients are fairly cheap
.
goingrey
Well-known member
My math was off 10x (hey, I said I'm no chemistI am gonna test this this fall. I got some clones rooting/rooted so as soon as I can multiply them again into many plants I am gonna start the citric acid. I am interested to see if it just washes the pm off like the lost coast or if an oil and soap have to be added also. I might just try to recreate the lost coast as all the ingredients are fairly cheap
). Edited the post, it is actually 1-3 g/l they used.Grower's Ally Fungicide seems even more concentrated, they state "Active Ingredients: Citric Acid 0.02%" which would be 20g/l.
I used both lost coast and flying skull when I was in California. Same thing as far as results. Flying skull is cheaper.
Also used micronized sulfur this last time. Only time since I got to desert that I've seen pm. Bro sent me a cut, by the time it arrived, there was a spot of pm on leaf. (EDIT: Did not see any when I put it in soil. It was the 3rd day that I saw it on a leaf. END EDIT) I nuked the entire veg room w the sulfur. Haven't seen it since.
A lot depends on size of garden man. Used to run rooms. Multiple moms in veg. Tend to 100+ plants at any given time. No getting it out of those. Take a break, kill everything off but clones of each, and spend 2-3 weeks following up
If small home garden, nuke everything w that sulfur man!
Also used micronized sulfur this last time. Only time since I got to desert that I've seen pm. Bro sent me a cut, by the time it arrived, there was a spot of pm on leaf. (EDIT: Did not see any when I put it in soil. It was the 3rd day that I saw it on a leaf. END EDIT) I nuked the entire veg room w the sulfur. Haven't seen it since.
A lot depends on size of garden man. Used to run rooms. Multiple moms in veg. Tend to 100+ plants at any given time. No getting it out of those. Take a break, kill everything off but clones of each, and spend 2-3 weeks following up
If small home garden, nuke everything w that sulfur man!
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mountainoutlaw
Well-known member
Trying the 1 tbl sod bicarb to gallon today, also gonna throw a small shot of 3 percent to kill any existing PM...this will be interesting.
Tynehead Tom
Well-known member
not to throw unwanted advice out there but killing PM is so easy and nothing in this thread gts the job done. The products mentioned in this thread might mask the fruiting of the PM , none of the things mentioned kill it.
I am no expert but I have followed a fella who does incredible research on the various forms of powdery mildew and especially the cannabis specific types. He has high powered microscopes that oberve the PM and shows the research in high resolution photos.
So he takes every single internet "bro science" method of eradicating PM and there is only one that actually works.
I know it works because for the first time i a decade , I got cannabis specific PM right near the end of my greenhouse run last season.
Fact is, once I saw the telltale white powdery spots it was too late to do anything. Luckily it was a very small part of my harvest affected. PM infects the plant and it takes 40 days from infection to fruiting which is the spore spots on the leaves. You can apply whatever you want to make those spots disappear but the parasite is still in/on your plants.
It is also a myth that PM is systemic....... people came to believe this because the products they were using were only masking the PM so it wasn't visible..... once the IPM stopped..... the PM returned making growers and bro science claim it was systemic.
CURING your plants and grow area of PM i simple as pie..... well as a former Baker I can say that curing... eradicting PM from your grow is even easier than baking a pie LOL
Wettable Sulphur..... Mix it up and spray your non flowering plants although do not use any oil based sprays prior to using the sulphur spray. It eradicates PM...... 100%
I used it ..... once and done and it's been over a year since I've seen PM and all my mother plants came from last years greenhouse stock. I sprayed the entire grow area in the greenhouse last fall and again this spring for good measure. I have not treated a single plant with any PM treatments this year and still NO PM.
I treated my infected moms and grow room (wash down) with the wettable sulphur solution and over winter and spring despite having absolutely packed grow rooms as I ramped up for the greenhouse...... Not a spec of PM.
So I am just trying to be helpful and save people a lot of time wasted...... get yourself some wettable sulphur powder.... it is easy to find and cheap to buy. Spray that shit and be done with it.
Again, do not use it in flower and do not use it after any sprays with oils in them.
I am no expert but I have followed a fella who does incredible research on the various forms of powdery mildew and especially the cannabis specific types. He has high powered microscopes that oberve the PM and shows the research in high resolution photos.
So he takes every single internet "bro science" method of eradicating PM and there is only one that actually works.
I know it works because for the first time i a decade , I got cannabis specific PM right near the end of my greenhouse run last season.
Fact is, once I saw the telltale white powdery spots it was too late to do anything. Luckily it was a very small part of my harvest affected. PM infects the plant and it takes 40 days from infection to fruiting which is the spore spots on the leaves. You can apply whatever you want to make those spots disappear but the parasite is still in/on your plants.
It is also a myth that PM is systemic....... people came to believe this because the products they were using were only masking the PM so it wasn't visible..... once the IPM stopped..... the PM returned making growers and bro science claim it was systemic.
CURING your plants and grow area of PM i simple as pie..... well as a former Baker I can say that curing... eradicting PM from your grow is even easier than baking a pie LOL
Wettable Sulphur..... Mix it up and spray your non flowering plants although do not use any oil based sprays prior to using the sulphur spray. It eradicates PM...... 100%
I used it ..... once and done and it's been over a year since I've seen PM and all my mother plants came from last years greenhouse stock. I sprayed the entire grow area in the greenhouse last fall and again this spring for good measure. I have not treated a single plant with any PM treatments this year and still NO PM.
I treated my infected moms and grow room (wash down) with the wettable sulphur solution and over winter and spring despite having absolutely packed grow rooms as I ramped up for the greenhouse...... Not a spec of PM.
So I am just trying to be helpful and save people a lot of time wasted...... get yourself some wettable sulphur powder.... it is easy to find and cheap to buy. Spray that shit and be done with it.
Again, do not use it in flower and do not use it after any sprays with oils in them.
goingrey
Well-known member
Ok, where can we find his research?
Btw, the single posted source was presented at a proper scientific conference and has 29 citations on Google Scholar. Not exactly bro science. They also had a link to the full text!
Of course, their claim is significant reduction not eradication.
Sulfur was already suggested by subrob but compared to citric acid has downsides like can't use in flower, not available for next to nothing at every grocery store...
