North American Fruit Explorers mailing list at ibiblio

["kieran or donna" <redherring@tnaccess.com>]

  >  Has anyone ever invented a blueberry for the Northern grower that
doesn't require acidic soil?  My soil is sandy, calcareous and has a vast
buffering potential to where it is not only difficult to make acidic but it
won't stay that way.  If I'm to grow blueberries, the plants should desire a
pH range of 6.5 to 7.5.  Does such a blueberry exist?
Jim Fruth

Whoa, wait a minute!  I remember something I read where some maverick wanted
to prove that blueberries don't "love acid" so much as they hate calcium.
Whoever it was ran the Magnesium level up to a ridiculously high pH,
something like an 8, and his blueberries thrived.  Mg buffers at 1.6X the
rate of Ca, so it takes less to run the pH up.  If you used magnesium
sulfate, Epsoms salts, you'd also get the advantage of the sulfur, not that
it would run the pH down very much.  If you can buy a small plant or two
cheap, I think it would be worthwhile to experiment.  If you got a A&L Labs
soil test done, you could find out if you already have a high ratio of Mg in
your soil.   I've read there are some very sticky clays in the middle of the
country that are seriously overloaded with Mg, that's what makes them so
sticky.  Most soil tests just tell you what your pH is, not what your Ca/Mg
level is, and that can be all important for plant health and soil stickiness
or drainage.  Jeff Poppen said that he had Ca deficiency in his truck crops,
and that liming didn't help.  then he realized that the nearest source of
lime was dolomite, and that for generations his farm had been limed with a
2:1 lime, when ideal is 6:1, esp for our clay soils.  (4:1 is better for
sandy soils)  He used a calcium phosphate and that helped a lot.  the
highest Ca:Mg lime we could find is a 33:1, we used that when we too had
used dolomite, and needed to get our Ca levels up with a minimum of pH
increase.  Donna