On Tue, 22 Apr 2003 16:06:16 -0500, zxcvbob
wrote:

Pat Meadows wrote:
On Tue, 22 Apr 2003 15:56:43 -0400, "mixter"
wrote:

i recently moved to a home with a few mature black walnut trees. i know
that tomatoe plants can't survive near them. unfortunately, the literature
i have doesn't say how far away i need to plant in order to get those nice
ripe jersey beefstakes.

does anyone here have a clue?

I've very successfully grown tomatoes about 75 feet from a
grove of black walnut trees. It didn't seem to hurt them.

I've no experience with closer distances.

I think you're pretty safe once you get out from under the dripline of
the tree. The juglone is exuded by the tree's roots.

I wish black walnut would retard the growth of *something.* I haven't
tried growing tomatoes in the middle of a back yard shaded by giant
black walnut trees, but everything else that can stand some shade does
just fine -- ivy, forsythia, violets, privet, iris, daffodils, mint,
lemon balm, ajuga, magnolia, gardenia, honeysuckle (vine),
blueberries, and weeds I can't identify.

I don't mean that I don't believe in juglone. An almost unreadable
Cornell page says, "Juglone is released by the roots of the plant, but
it is not very soluble in water and doesn't travel far in the soil.
Some examples of plants that may be affected are tomatoes, black
alders, alfalfa, apple trees, corns, beans, potatoes and many others."

I wonder how much the effect of summer shade contributes to this?