pH testing and adjustment

[Muddy Boots]

Its a few years since I tested the pH on my allotment and so I have now checked the plot for this year's planting of greens to see if lime needs to be added. At a reading of 7.5 no lime is needed (apart from being a bit late to do so).

However, in the test kit was a list of pH ranges for specific plants. I was surprised to see that potatoes need an acid soil (obviously news to me) in the range pH 4.5 - 6.0.

I don't have a problem growing potatoes but I am curious what I would need to add to this years potato plot to bring it within that range. Then for next year's roatation it would need to be returned to a less acid range and the new potato plot adjusted; which seems all too much bother.

[Nicos]

We grow on a peat soil with a pH of anything between 3 and 7 depending on where the soil is tested. These readings can occur only 6 feet apart and vary throughout the year depending on the height of the water table. Leaching of nutrients is also a problem because of this. However, manuring and liming 2-3 weeks before sowing has produced wonderful results over the past 2 years.We have grown a huge variety of crops with great success, yet we only lime sparingly over the whole plot (with larger amounts on the brassica patch). I wouldn't get to bogged down with the idea of altering the pH unless you want to grow a particular crop with specific needs. Will the farm manure added to the potatoes not make the soil more acidic?