Composting rhubarb leaves
Many folks have been concerned about adding rhubarb leaves to their compost piles. If the leaves are poisonous, they must be bad for compost as well, since rhubarb stalks contain a high concentration of oxalic acid which slightly toxic, right? What actually occurs when rhubarb is added to a compost pile is that the oxalic acid is mostly broken down, diluted and pH balanced rather quickly. People do not eat compost piles as a rule anyway, and even if a child were to eat compost dirt, there would be problems other than from and remaining oxalic acid from the decomposing rhubarb stalks. Experience has shown that the level of acid does not inhibit the microbial action of composting. Compost piles which were nearly all rhubarb leaves and stalks have decomposed very nicely and the compost has behaved like ordinary compost and no inhibition of plant growth was noticed from the compost.
Please note that some items are a problem for composting including: omnivore (cat and dog) pet feces (composting it is fine, just don't use the compost for plants that you will eat), diapers, meat scraps, and treated lumber (older treated lumber contained chromated copper arsenate).
- Rhubarb, http://www.lysator.liu.se/ftp/pub/gardening/Edibles/rhubarb, An email From: JOHN HEIM, Subject: Rhubarb care, Date: 26 May 92 19:03:59 GMT