Allotments 4 All

hi folks!
read on here that a piece of rhubarb underneath brassicas helps to prevent something called clubroot.
however, also read on here that rhubarb has toxins in at this time of year so, with my dobies collection due any day now.....
is it still ok to put rhubarb in the planting whole?
and (since i don't think i have enough for all fifty plants) do some need it more than others?
i only got my plot this year and don't know what was grown where last year so may be inadvertently failing to rotate.
thanks, Tara xx

Rhubarb has oxalic acid in the leaves not the stems. I wouldn't worry about putting it under your brassicas as they're not actually eating the rhubarb anyway. I compost the leaves, use the acid to treat behhives for mites, and have never had a problem. Unlike conventional miticides and other organic acids, I've never heard of a beekeeper being poisoned by oxalic either.

Quote from: daveandtara on August 27, 2005, 11:05:25
hi folks!
read on here that a piece of rhubarb underneath brassicas helps to prevent something called clubroot.
however, also read on here that rhubarb has toxins in at this time of year so, with my dobies collection due any day now.....
is it still ok to put rhubarb in the planting whole?
and (since i don't think i have enough for all fifty plants) do some need it more than others?
thanks, Tara xx

I have never seen any peer reviewed research to indicate that rhubarb prevents the growth of club root but I have seen many anecdotal reports of it's apparent ability to suppress the fungus. This site however,:
http://www.rhubarbinfo.com/rhubarb-poison.html
suggests that there may be other compounds involved besides oxalic acid in it's toxicity.
If oxalic acid is the active compound then this site:
http://growingtaste.com/oxalicacid.shtml
indicates many other common plants that can be sustituted for rhubarb. While you may not wish to sacrifice parsley, with it's equivalent concentration of oxalic acid, to provide protection, lambs quarters, (fat hen in the U.K. I believe, [botanically Chenopodium album], would be a far more effective substitute and you would need substantially less of it!