In article , "Guyz-N-Flyz"
wrote:

I think my uncle received a load of black walnut leaf mulch; consequently,
his asparagus, Brussels sprouts, cucumbers, tomatoes and other veggies are
dying.

Is there anything that will neutralize the affects of juglone toxicity, once
he removes the offending leaf mulch?

TIA,

Mark

Composting breaks down the juglone, so if you mix the leaves with soil &
keep it moist & add some nitrogen to speed up the process it will take
care of itself at the speed of composting, even without entirely removing
the leaves.

Since you indicate that your uncle will be raking out the walnut leaves,
that'll speed up the process dramatically. He can follow the removal with
deep watering now & then to flush any lingering juglone deeper into the
soil, where bacteria will take care of it before too long. Presumedly he
won't be planting any new veggies this time of year anyway, & the area
should have repaired itself by next spring's planting time. He's not
committed any end-of-world catastrophic garden booboo, it's something
gardens can pretty much repair on their own.

You say, however, "I think" it was black walnut -- if no one's sure there
were walnut leaves involved, there could be some other problem. I mulch
with fallen leaves of chokecherry & sweet cherry & plum trees which all
have juglone & this does't bother the plants at all, not even the azaleas
which can be juglone-sensitive, but of course the concentrations are a
fraction that of walnut, & I don't use these leaves for anything as
senstive as tomatoes.

-paghat the ratgirl

--
"Of what are you afraid, my child?" inquired the kindly teacher.
"Oh, sir! The flowers, they are wild," replied the timid creature.
-from Peter Newell's "Wild Flowers"
Visit the Garden of Paghat the Ratgirl: http://www.paghat.com