Why can't you put rhubarb leaves on the compost heap?

It turns out you can! While we don't advise eating rhubarb leaves, it turns out that you can compost them; we explain why here.


Asked by: Chai Jin, Poole

Rhubarb leaves contain oxalic acid, which is corrosive and a kidney toxin, but this has no significant effect on soil micro-organisms. The leaves will decompose perfectly well as the amount of oxalic acid is low and the molecule doesn't survive well outside of the plant cells. Eating plants grown in rhubarb-leaf compost is also perfectly safe.

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