Vapam Damage

DStoerz dstoerz at
Sat Apr 20 21:48:47 EST 1996

I operate a small greenhouse biusiness and am having a problem with my
petunia crop.  The plants in the plug trays are very chlorotic and appear
as though they have a severe nutrient deficiency.  However, because I have
been maintaining my normal fertilization program, I don't believe
nutrients are the problem.  Most of the affected plants are continuing to
grow, but they look aweful.  Even after transplanting, they do not

I used a tank for fertilizing the plants that at one time had been used
for mixing vapam.  Any vapam residue that remained in the tank would have
been extremely small.  Does anyone know if petunias are especially
suseptible to damage from vapam?  

Only the petunias are affected -- marigolds, pansies, lobelia, tomatoes,
and many other plant types are unaffected.  Petunias that were not
fertilized using this tank are normal.

Thank you for any insights. 

Dale Stoerzinger
DStoerz at

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