[Jim the builder]

Have just purchased some blueberry bushes and Ive been told that they require an acid soil, is this correct and if yes how would I go about increasing the soils acidity

[arugula]

Yes blueberries do require acidic soil. Here are John's notes on soil pH:

http://www.allotment-garden.org/articles2/Soil_PH_and_Its_Effect_on_Your_Garden.php

[bigben]

I dont know where you plan to plant the bushes but if it is just into the soil you face an ongoing battle to keep the pH low as the surrounding soil keeps working to raise it back to neutral. Some people resort to planting in big pots or partly lining the hole they plant in with plastic to reduce the effect of the surrounding soil. It also helps keep the bush damp which they like. You will needs some holes so it is not waterlogged.

[JayG]

The easiest way is to test the pH of your soil and hope that it's around 5 - unfortunately that's a fairly unlikely outcome in this country.

Commonest way is to plant in ericaceous compost, either in a large pot (some bury the pot in the garden to provide more consistent root temperatures) or in a large hole filled with ericaceous compost.

Others (like me!) start off with about the right pH when planting and then find out about 5 years later that it's crept back up to about neutral!  
Without digging them up and starting again it's then a matter of adding sulphur chips, ammonium sulphate, and mulches which will leach organic acids into the soil as they decompose (pine needles/moss peat, or both.)
Much more difficult lowering pH than raising it but I expect it to work eventually!  

[bigben]

Anyone know if adding citrus fruit peel as a mulch would lower the pH for blueberries? I have been thinking about simply chopping it and adding it to the raised bed I have my blueberries in rather than the general compost heap.

[JayG]

Don't know how much citric acid is in the peel rather than the juice Bigben (wouldn't hurt to try, and if nothing else your blueberry bed would at least smell nice!) 

[Trillium]

There are acidifying fertilizers available that will help, but in reality, I find mine aren't so fussy about soil acidity as they are of regular manuring and keeping the soil relatively damp (never soggy).  Mine are doing so well now that I must cage them in against those thieving birds 

[digalotty]

my neighbour puts his blueberry bushes in a hole lined with polythene so he can regulate the plants seperately.
although the person who had my plot before me had amazing blueberrys and he just stuck em in and let them decide weather they liked it or not

[allotment south wales]

You can buy ericaceous compost suitable for blueberrys and Rhododendrons  acid loving plants

also availible to buy suitable fertilizer / feeds for acid loving plants that would be suitable for blueberrys..