On 3 Wrz, 09:00, "David Hare-Scott" wrote:

Are you sure yourmeteris accurate? The cheaper metal probe type can be
confused by variations in moisture and dissolved salts. Perhaps you can
callibrate it against a dye indicator system.

IMHO that's most likely cause of problems. Correct procedure of soil
pH measurements calls for glass (or MOSFET) pH electrode (see
procedure outlined he http://www.ph-meter.info/pH-measurem...er-procedures).
Calibration of metal type probe against indicator won't help, as the
probe result will change with the soil humidity level, while
idndicator results will not.

Mr.pH
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