Any experiences with rhubarb as an understory plant in food forests ?
I wonder if the toxicity of leaves inhibits growth of other plants.
I've got lots of rhubarb growing as a guild plant, in full-sun polycultures, and I also use it as part of a grass barrier that includes yarrow, comfrey, clover, and datura (very effective at stopping grass). It does prefer full sun over the shade of a tree guild, but it still grows okay in art shade. I've never seen any toxic effects; everything growing around it does just fine.. The toxin in rhubarb is, I believe, oxalic acid, which is tough on people but is easily broken down by soil organisms.
Toby
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