Reduce pH from high alkaline
Now several parts of my plot are becoming clear of produce I thought I'd start to look at liming / manuring so have purchased a pH meter - have checked over most of the plot and have found the pH readings are an average of 9 which is very alkaline - have been looking at what to use to reduce the pH and the only real thing I can find is Sulphur chips which are ok for a small garden area but very expensive to apply all over an allotment has anyone any ideas of cheaper / better way to achieve a satisfactory result
Runnerbean
There are no specific chemicals which can safely be applied to the soil to make it more acid, so the acids must come from increased quantities of organic matter as they are decomposed by soil bacteria. The use of acid natured fertilisers will also help.
The speed at which organic matter breaks down is affected by soil type, temperature and bacterial content, so the amounts required can only be approximated.
Organic methods
To reduce the pH by approximately 1.0 unit, use:
Peat - dug into your soil at the rate of approximately 2.5 lbs per square yard
Compost - dug into your soil at the rate of approximately 14 lbs per square yard
Manure - dug into your soil at the rate of approximately 5 lbs per square yard
I hope that helps.