Last year I discovered this garden technique of making an insect repellent spray for your plants using the leaves of rhubarb plant.
A family member had asked for some rhubarb to give to her grandmother Margie, with the unusual request of leaving the leaves on the stem.
Usually when I harvest the rhubarb, I cut off the leaves and dispose of them immediately as they can be harmful to animals due to the toxins they contain.
I asked to find out more as to what the leaves would be used for and Margie explained it is used as a plant spray to prevent aphids.
So, with a quick google search I found there is a lot of research to support the claim.
Rhubarb leaves contain a natural low dose of oxalic acid. Although these leaves are highly toxic for consumption their toxicity has its benefits. The oxalic acid acts as a very mild pesticide. I don’t like using the term pesticide because I know how harmful the use can be in the garden, especially to our much-needed bees and pollinators.
However, because there is such a low volume of oxalic acid in the mixture it remains harmless to our bees. In fact, rhubarb spray is often used to treat bees for varroa, (a mite which infects the apiary) as it has no affect on the bees or their honey.
Last spring was the first time I used this mixture. I used it on my roses to treat the greenfly and let me tell you I was impressed.
It’s not as instantaneous as chemical treatments but within two weeks of treatment the roses were free of greenfly and remained that way with the occasional spray throughout the summer. So, although it takes a little longer than a regular pesticide, I think it is definitely worth the effort to avoid harming any of the much-needed pollinators
The rose garden is often teeming with bees and butterflies and the use of the rhubarb spray didn’t disrupt their activity at all which was a major win for me.
The mixture is very quick and easy to make and I would personally recommend you at least give it a go to see the benefits for yourself.
Rhubarb leaf spray recipe:
1. Half fill a saucepan with rhubarb leaves
2. Fill remaining space with water and bring to the boil.
3. Allow the leaves to simmer for 5 minutes before allowing to cool.
4. Strain off the leaves and use a spray bottle to apply it to your plants.
I am aware that unless you grow your own rhubarb you may not have access to rhubarb leaves, but if anyone wants to reach out, I’m happy to share from the rhubarb patch at Turra Lodge Farm.
