I bit more on copper
True pumpkin seeds high in zinc, but also source for copper.
All plants require adequate copper as it is necessary for photosynthesis.
Some crops much more sensitive to copper levels than others...certain grain
crops and onions especially.
High humus levels (such as in my patch and most giant pumpkin grower's
patches) tend to result in low available copper levels. Effects of copper
deficiency may not be apparent upon observation of the plant, but repletion
of low levels may supposedly result in significant crop improvement.
I was misled about copper deficiency causing chlorosis from one web site ...
it is actually copper toxicity that may result in chlorosis. This is
because excess copper may prevent uptake of iron. Ongoing use of copper
fungicides or excess copper supplementation can lead to a cumulative copper
toxicity, and because copper leaches out of soil poorly it may take years
for toxic levels to diminish.
My apologies for any confusion on the chlorosis issue.
Also, according to soil fertility specialist at the Ontario growers meeting
in 2001, Boron is necessary for seed development. I haven't yet been able
to establish the possible role of copper in seed or fruit development...any
other thoughts on this or pointers to good online or written resources would
be appreciated.
Thanks much,
Chris
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Chris Wilbers
Springfield, MO / Zone 6
Growing pumpkins since 1996
Personal best 520.4 lb. (2000)
So then neither the one who plants nor the one who waters is anything, but
God who causes the growth. -- I Corinthians 3:7
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n*@sofnet.com
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