Found this while looking into Castor Oil. CA Pesticide Chart

MAGpie81

Well-Known Member
I found an old bottle of fungicide for topical human use, and was curious about it’s active ingredient, undecylenic acid.
I had tried some on a little athlete’s toe, and found it worked great after one application.
So I discovered it’s made from castor bean oil, which then led me to the above chart, and also other-sited info on it having been used for a long time as a fungicide.
https://ganeshorganics.org/product/fabol-30/,
Has anyone made any IPM sprays using castor oil? At what plant stage did they use it?
I’m hoping to mix some with my usual rosemary tea solution.
Also- has anyone applied as a direct topical on problem PM spots? This I may try.
 
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MAGpie81

Well-Known Member
Most oils work as a fungicide. The only problem is you can't spray in flower.
Yeah, that’s my only concern. That’s why I may test as a topical on a little runt I’m just letting go. It was monster cropped and so has some revegged flower and has been shown prone to pm, which I’ve tested various solutions on; good experimental plant.
Also, if you read up on castor oil and other specific plant oils like geranium or rosemary, they do have specific chemicals shown to fight fungus/pests.
 

MAGpie81

Well-Known Member
I wouldn't use castor oil on cannabis. Look up Ricin. It's made from castor bean oil.
Haha, that’s funny because I noticed “Ricinium(?)” in it’s latin name and made that mental connection.
I’ll research whether it’s systemic; see if it spreads throughout the plant even if applied in a localized, topical manner.
 

xtsho

Well-Known Member
Haha, that’s funny because I noticed “Ricinium(?)” in it’s latin name and made that mental connection.
I’ll research whether it’s systemic; see if it spreads throughout the plant even if applied in a localized, topical manner.
My father used to grow the plant years ago. It's a beautiful looking plant but poison. Especially the beans/seeds. 4 or 5 can kill an adult. Caution is advised.

I'd suggest a different oil. Sesame oil is a good fungicide. It's what I've started using instead of neem. The results have been exceptional. Plus it's non-toxic. I switched from neem after some testing showed results so just one less thing to buy since I always have sesame oil on hand for cooking. The fact that you can eat it makes me feel better about spraying it on my cannabis. I could drink a glass of sesame oil and the only ill effects would probably be some leaky bowels for a day or so. :mrgreen:
 

MAGpie81

Well-Known Member
My father used to grow the plant years ago. It's a beautiful looking plant but poison. Especially the beans/seeds. 4 or 5 can kill an adult. Caution is advised.

I'd suggest a different oil. Sesame oil is a good fungicide. It's what I've started using instead of neem. The results have been exceptional. Plus it's non-toxic. I switched from neem after some testing showed results so just one less thing to buy since I always have sesame oil on hand for cooking. The fact that you can eat it makes me feel better about spraying it on my cannabis. I could drink a glass of sesame oil and the only ill effects would probably be some leaky bowels for a day or so. :mrgreen:
Great advice, m’friend.
Sesame oil is listed as the first ingredient in this product “Organicide” I use during veg. It’s other ingredient is some kind of fish emulsion, so not going to use even in early flower.

May mix some sesame oil with rosemary tea, which I use with good results against mites. Also- had a wide-glass flower holder bowl with water that I left fresh rosemary sprigs sitting in, in the sun, for weeks. It briefly sprung a tiny patch of mold on a small part above the water level, which quickly died out after splashing the surrounding rosemary “tea” on. Rosemary is another common additive in pro-strength approved organic pesti-fungi-cides.

So, thanks for your input- I think I’ll try Rosemary bloomed in hot Sesame oil, perhaps tested first as a topical on my “guinea-pig” plant:bigjoint:
 

xtsho

Well-Known Member
Great advice, m’friend.
Sesame oil is listed as the first ingredient in this product “Organicide” I use during veg. It’s other ingredient is some kind of fish emulsion, so not going to use even in early flower.

May mix some sesame oil with rosemary tea, which I use with good results against mites. Also- had a wide-glass flower holder bowl with water that I left fresh rosemary sprigs sitting in, in the sun, for weeks. It briefly sprung a tiny patch of mold on a small part above the water level, which quickly died out after splashing the surrounding rosemary “tea” on. Rosemary is another common additive in pro-strength approved organic pesti-fungi-cides.

So, thanks for your input- I think I’ll try Rosemary bloomed in hot Sesame oil, perhaps tested first as a topical on my “guinea-pig” plant:bigjoint:
I've used rosemary for years.

I have a big rosemary bush. I've made tea within the last year. I haven't made any for some time. The sesame oil, citric acid, and potassium silicate has been working great at preventing everything. Its amazing how just a few simple things can do so much.
 

Cycad

Well-Known Member
Most oils and pretty much all EOs are fungicidal. However I should imagine that spraying them with geraniol or peppermint oil is for sure going to affect the terp profile!
 

MAGpie81

Well-Known Member
Most oils and pretty much all EOs are fungicidal. However I should imagine that spraying them with geraniol or peppermint oil is for sure going to affect the terp profile!
The tricky thing is- you want some fungal action because it spurs the development of terpenes which are another weapon the plant uses to combat infection. Think of them like you would turpentine, a volatile organic compound (VOC) that acts as a solvent, and is made from pine tree “terpenes” (according to ye olde Wicki. “terpene” is an “outdated” abbrev. of “turpentine”).
Terpenes form to dissuade insects/animals from eating the plant, and inhibits fungal growth. So, yeah, most herbaceous oils are probably pretty good at controlling fungal outbreaks.
Of note- I heard on one of my nerdcasts (probably “Cannabis Cultivation & Science” podcast) that by the time you see PM it’s already been growing inside the plant for close to a month. So- take initiative before any symptoms arise!
 
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