"Jeff Layman" wrote in message
Steve Wolstenholme wrote:

Having just tested my allotment soil, it was coming out at a ph of
about 8+, however I didn't have distilled water to hand so possibly
the local water skewed the true reading, is this likely, the water on
it's own was fairly alkaline?.
Anyhow, should it be required, what do you add to the soil to make it
more acidic?

You can make soil more acid with an annual dose of Sequestrine of
Iron.

Iron sequestrene has no effect on soil acidity. It is simply a soluble
form of iron which can be taken up by plants in less than ideal (ie
alkaline) conditions. See the link in Stuart Noble's post for things
which can acidify soil.

This situation has recently been covered in the TV show 'Gardening
Australia'. The specific situation was that very alkaline water was causing
problems in a garden. The show had previously visited the garden and the
roses were getting scorched leaf margins as a direct result of the
alkalinity. Water used on the garden came from a bore and had a pH of 8.5.
Apparently spreading Sulphur in all areas of the garden fixed the problem
(this is a big garden).
http://www.abc.net.au/gardening/stories/s2169781.htm