Hi all,- as i harvest the rhubarb for my wine making shed i was wondering,- could these discarded Rhubarb leaves be turned into a pesticide to keep the aphids/caterpillers at bay?
Regards,
Mark.
Rhubarb Leaves - can an organic pesticide be made from them?
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Hello Mark - have a look at this link - http://www.pan-uk.org/lap/alt~dir/aphids.htm
Covers how to make a rhubarb solution and rhubarb soap from the leaves, to control aphids. You will need to scroll down quite a way to get to them. Not tried this myself, so will be interested to hear how you get on.
Covers how to make a rhubarb solution and rhubarb soap from the leaves, to control aphids. You will need to scroll down quite a way to get to them. Not tried this myself, so will be interested to hear how you get on.
The cow is of the bovine ilk
One end is moo, the other, milk.
One end is moo, the other, milk.
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oldherbaceous
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Chez that was clever, get Mark to try it just in case it kills the plants. 
Kind regards Old Herbaceous.
It will either rain or get dark.
Kind regards Old Herbaceous.
It will either rain or get dark.
Heh! Heh!
I`ve used the garlic/soap solution already,and yes it does seem to work.
I`ve used an old fag end recipie,and that kills everything that moves
So i will now find an old pan,and try the Rhubarb solution,and try to find that "in-between"solution i`m looking for.
Thanks for the advice guys,- i`ll send Chez the bill for a new pan
Regards,
Mark.
I`ve used the garlic/soap solution already,and yes it does seem to work.
I`ve used an old fag end recipie,and that kills everything that moves
So i will now find an old pan,and try the Rhubarb solution,and try to find that "in-between"solution i`m looking for.
Thanks for the advice guys,- i`ll send Chez the bill for a new pan
Regards,
Mark.
I`m not "young enough"to know everything!
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Cider Boys
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Hello Mark
Yes you can use Rhubarb leaves to control aphids, I have used it in the past with moderate success on blackfly on beans.
Recipe as described by Lawrence D Hills (one of the organic founders).
1 lb of rhubarb leaves simmering in 1 qt of water for 1/2 hour.
Dilute with 2 qt of cold water and spray.
Always use within 24 hours.
Cheers
Barney
Yes you can use Rhubarb leaves to control aphids, I have used it in the past with moderate success on blackfly on beans.
Recipe as described by Lawrence D Hills (one of the organic founders).
1 lb of rhubarb leaves simmering in 1 qt of water for 1/2 hour.
Dilute with 2 qt of cold water and spray.
Always use within 24 hours.
Cheers
Barney
Hello Old Herb and Mark - true, as it doesn't say anything in that link about the state the plants are left in . Since posting that, I have wondered if it is a good spray to use on vegetables (being so toxic) or is best left to ornamentals? I suppose that fact that it's water-soluble means it should be okay if veg are washed well before consumption(?) If I don't get the bill for the new pan, I will know I was right . Ooh, scaring myself now .
. Since posting that, I have wondered if it is a good spray to use on vegetables (being so toxic) or is best left to ornamentals? I suppose that fact that it's water-soluble means it should be okay if veg are washed well before consumption(?) If I don't get the bill for the new pan, I will know I was right . Ooh, scaring myself now .The cow is of the bovine ilk
One end is moo, the other, milk.
One end is moo, the other, milk.
Boiling rhubarb leaves will clean out your pans beautifully...I've often used them when my pressure cooker has boiled dry and left a burnt coating on the inside. I'm not sure about not stick coated pans!
However I've never used the rhubarb for an insecticide.
However I've never used the rhubarb for an insecticide.
I don't suffer from insanity .... I enjoy it!
Vivianne
Vivianne
Hi Chez,
I assume that you eat Spinach quite cheerfully which has a high percentage of Oxalic Acid so I really do not think the concentration of Oxalic Acid in the Rhubarb leaf spray is that high and it is not systemic and assuming you do not spray and then eat something within a few days you should be very safe.
This method was used to my knowledge back in the 1940's in most gardens.
I assume that you eat Spinach quite cheerfully which has a high percentage of Oxalic Acid so I really do not think the concentration of Oxalic Acid in the Rhubarb leaf spray is that high and it is not systemic and assuming you do not spray and then eat something within a few days you should be very safe.
This method was used to my knowledge back in the 1940's in most gardens.
JB.
Johnboy, yes I love spinach! But I didn't know or at least had never thought about it containing oxalic acid until you and Sally Wright (I think) were posting about it. Was it you? I can't remember the gist of the thread now, but anyway as a result, I googled for foods containing oxalic acid and a website (can't recall which now) said because of the amount of oxalic acid contained in spinach, don't eat too much of it. I still do though. Nothing like roast beef, spinach and horseradish sauce sandwiches 
. I suppose it was the warning on the rhubarb 'pesticide' recipe to keep away from children combined with the solution being recommended for roses, with no mention of veg. But then we're not talking about drinking it. Do you know why it went out of favour? Was it not that effective compared to other methods? Barney, would you use it again?
I am very happy with how marigolds controlled (more like eliminated) aphids from both our broad beans and tomatoes last year, so will stick with that method of control for now. Unless of course Mark comes back with a glowing recommendation.
. I suppose it was the warning on the rhubarb 'pesticide' recipe to keep away from children combined with the solution being recommended for roses, with no mention of veg. But then we're not talking about drinking it. Do you know why it went out of favour? Was it not that effective compared to other methods? Barney, would you use it again?
I am very happy with how marigolds controlled (more like eliminated) aphids from both our broad beans and tomatoes last year, so will stick with that method of control for now. Unless of course Mark comes back with a glowing recommendation.
The cow is of the bovine ilk
One end is moo, the other, milk.
One end is moo, the other, milk.
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Cider Boys
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Hello Chez
Yes I will use it again, it is not so convenient as a commercial insecticide but it is cheaper and organic.
The last time I used the Rhubarb mixture was on my Runner Beans, again effected with blackfly and it did help control them.
Like Johnboy I have always considered it an established old timers home made pesticide. Elder leaves can be used in the same way offering, hydrocyanic acid in a dilute extract.
Rhubarb and Elder solutions are safe for bees and both break down in the soil.
However Rhubarb stalks taste better than Elder stalks!
Barney
Yes I will use it again, it is not so convenient as a commercial insecticide but it is cheaper and organic.
The last time I used the Rhubarb mixture was on my Runner Beans, again effected with blackfly and it did help control them.
Like Johnboy I have always considered it an established old timers home made pesticide. Elder leaves can be used in the same way offering, hydrocyanic acid in a dilute extract.
Rhubarb and Elder solutions are safe for bees and both break down in the soil.
However Rhubarb stalks taste better than Elder stalks!
Barney
Hi Chez,
Certainly when Rhubarb leaves have been made up as a pesticide then the precautions that should be taken are those of any other pesticde. The R. solution should be made and used and not stored. I think the reason that it fell out of favour is the time old story. It takes time to prepare it and when Chemical Pesticides came in they were the easy way out with no messing about.
As Barney says this method is exceedingly effective for Blackfly on Beans, Both Broad and Runner.
When you say Marigolds do you mean Tagetes or Calendula. Calendula attract Black fly and whereas in the past I have simply picked off the affected parts from the Calendula you could now spray them but feel they would lose their attractant value so as I write I am going off the idea!
Certainly when Rhubarb leaves have been made up as a pesticide then the precautions that should be taken are those of any other pesticde. The R. solution should be made and used and not stored. I think the reason that it fell out of favour is the time old story. It takes time to prepare it and when Chemical Pesticides came in they were the easy way out with no messing about.
As Barney says this method is exceedingly effective for Blackfly on Beans, Both Broad and Runner.
When you say Marigolds do you mean Tagetes or Calendula. Calendula attract Black fly and whereas in the past I have simply picked off the affected parts from the Calendula you could now spray them but feel they would lose their attractant value so as I write I am going off the idea!
JB.
Hello Johnboy - I meant companion planting with French marigolds, so the Tagetes family. There is no need to spray them, as Tagetes work to repel blackfly and greenfly, by producing an offensive scent. So nothing to spray. Impressive results last year, so I will see how we get on this season.
Have you thought about trying French marigolds? No need to pick anything off with them. With your calendula experience it would be interesting to see how they compare in practice. Hmmm... perhaps wait until I can confirm another successful season. Just in case it was an anomaly and not the marigolds at all. Perish the thought. 
Have you thought about trying French marigolds? No need to pick anything off with them. With your calendula experience it would be interesting to see how they compare in practice. Hmmm... perhaps wait until I can confirm another successful season. Just in case it was an anomaly and not the marigolds at all.
Perish the thought. The cow is of the bovine ilk
One end is moo, the other, milk.
One end is moo, the other, milk.
Hi Chez,
I think that you will find that Jenny Green uses Tagetes, if my memory serves me right, and has used them to ward off things, including White Fly, from her Greenhouse to, it appears, very good results.
Calendula have the opposite effect and if there Aphids around, especially Blackfly, they are attracted to them rather than your crop. This method I prefer as it means that I can prevent them multiplying and do not just push them somebody elses way. I find that Nastursiums have the same effect and I simply pick off affected leaves and destoy then complete with Aphids.
I think that you will find that Jenny Green uses Tagetes, if my memory serves me right, and has used them to ward off things, including White Fly, from her Greenhouse to, it appears, very good results.
Calendula have the opposite effect and if there Aphids around, especially Blackfly, they are attracted to them rather than your crop. This method I prefer as it means that I can prevent them multiplying and do not just push them somebody elses way. I find that Nastursiums have the same effect and I simply pick off affected leaves and destoy then complete with Aphids.
JB.
I find all these postings interesting. However I puzzle about the point being made that a chemical such as oxalic acid can be dangerous in one context yet safe if it is declared to be Organic, or is it organic? I'll leave you lot to sort it out. Back to the simple things in life with my cup of caffein and H2O. 'Bye! :?
Allan
Allan
Hi Chez,
Here is a website that is a bit alarmist but if you read it through it is quite informative.
www.pfaf.org/database/plants.php?Spinacia+oleracea
It actually gives a Hazard warning at the begining which I think is a little over the top.
I find that people like me with Arthritis should not eat it. The strange thing is that when I was in Hospital having just had a replacement knee my special diet included Spinach twice in the period of 8 days I was in there.
Here is a website that is a bit alarmist but if you read it through it is quite informative.
www.pfaf.org/database/plants.php?Spinacia+oleracea
It actually gives a Hazard warning at the begining which I think is a little over the top.
I find that people like me with Arthritis should not eat it. The strange thing is that when I was in Hospital having just had a replacement knee my special diet included Spinach twice in the period of 8 days I was in there.
JB.