Do poisonous plants tend to secrete poisons into the soil or in some other way contaminate the plants that grow around them? I'm especially thinking of root vegetables, but I haven't been able to find any kind of reference.

-- Jessie Stickgold-Sarah (sorokin@alum.mit.edu), March 12, 2000

Answers

We tried planting jabanero peppers (which some people would think of as non-edible) between our tomatoes and the fence to keep the rabbits away. They ate all the leaves off the pepper plants and never touched the tomatoes. Go figure.

-- Colin (cfmckin@uswest.com), March 13, 2000.

Some do, some don't. Right offhand I can tell you that you won't grow anything near a Black Walnut tree. Well maybe there are a few but the juice it secretes is poisonous to most other plants. Another one....can't even remember but acts as an herbicide! I know, I'm real helpful. I know that you can search for "companion+planting" in like, altavista and get lots of articles. Hope at least some of that he

-- Renee (justme@justme.org), March 14, 2000.

I would think it would depend on the specific poisonous plants you have in mind, because plants are poisonous in different ways. For instance, narcissus bulbs are moderately poisonous, but we had them under our vegetable garden last year, and no one died. I don't think anyone did, anyway. But some other plants might secrete poisons into the ground, which is what you're worried about.

I would ask at a nursery. Be prepared, though, because you'll find that the information about poisonous plants isn't as complete as you'd expect. I think Cornell has a good web site -- I'll try to find it -- but you'll find that different sources will give you completely different information about poisonous plants, because the evidence is mostly anecdotal.

-- Beth (beth@xeney.com), March 16, 2000.