Market Farming

[Peter Worsley <pwors AT svn.net>]

I have a potential problem and a question-

I use all drip irrigation, pumping water from a farm pond. I've noticed
that over a period of a couple months, a whitish deposit accumulates
around my emitters; eventually the entire top of my raised beds become
white and crusty. I assume this is some kind of a mineral deposit. I use
a 155 mesh filter, and one of those magnetic water conditioners that
strap around the outside of a 1" plastic pipe. The deposits dissapear
when tilling between crops, but eventually reappear. I've also noticed
that the ph of my soil is gradually increasing- this year for the first
time I had to add sulfur to lower the ph. Most of my crops seem ok,
except those in a certain area, which doesn't drain quite as well as
elsewhere. There, lettuce appears a little stunted, leaves less shiny,
taste a little bitter. I have sandy silt loam soil and am in a creek
valley which occasionally floods for short periods in winter. Soil tests
show only that the ph is high- everything else seems within normal
limits. My question is- Are raised ph and mineral deposits related? I
must assume they are. Any suggestions about what's going on and what can
be done about it? I'm organic, by the way. I'd especially appreciate
hearing from anyone in coastal Northern California (Marin or Sonoma
counties) which is where I am. Thanks- Peter