Hi Dick,
The soil test recommendations are for the crop, not based on how much N is
in the soil. This is because N is highly mobile so what's here today could be
gone (day after) tomorrow if there's a lot of rain.
What's the soil like in his garden? I can't help but wonder if the corn is
drowning. I grew up in Carlton Co., near Aitkin Co. and our garden soil was
"Automba loam" but it was awfully heavy--almost clay. Nothing like the sandy
loam I have here on the Anoka sandplain in my yard in Crystal.
Marginal necrosis is symptomatic of root rot/excess water as the new
growth/edges of the leaves have first dibs on moisture. Consequently, excess
soil moisture will show up as marginal necrosis.
Have you had a lot of rain?? Gardens need about 1" of moisture. I suspect
he's overwatering.
Encourage him to work organic material into his soil. If he has heavy/clay
soil, the clay particles will bind to the OM and form colloids which makes
bigger airspaces in the soil. If his soil is coarser/sandy the OM will hold water
and nutrients in the root zone. Given your short growing season, corn is
probably out of the question for this year. Bummer.
HTH,
Beth Jarvis
Yard & Garden Line
> I received a call from a man who has attempted to plant corn 3 times since early
> May, most recently June 10th and the leaves of each planting after reaching 5-6"
> begin to turn brown on the edges, then die. He indicated that he waters
> faithfully and this year had a soil test done by the U of M. It was suggested
> that he needed additional nitrogen, which he has added based on the
> recommendation of the soil test report. I would appreciate your assistance.
> Dick Aitkin/Crow Wing MG
