Sour soil?

 Three of my flower beds, two of them borders, have failed to produce healthy
salvias, geraniums and busy lizzies this year. In previous years I have had
an excellent show. I plan to deep dig (heavy south London clay) these plots
in the autumn. What should I add to the soil to re-invigorate it?
Alistair

 
"Alistair Macdonald"  wrote

Did you water enough this year|? Its been a daily job on our allotment and I
can't be too far away. Our garden is dreadful this year, I'm just about
keeping stuff alive.

Usually clay needs plenty of organic stuff, well rotted horse manure,
mushroom compost, Council recycled compost etc. and you could use some
Gypsum to break up the clay too (Builders plaster if you can't find the real
stuff) or after testing the pH, if it's well below 7, some lime. Clay is
usually a very fertile soil as it holds on to nutrients and doesn't let them
wash through like a sandy soil would.
Might be worth having your soil tested to check what is wrong, I believe the
RHS do it for a price.

--
Regards
Bob Hobden
17mls W. of London.UK

 I have taken in all the advice concerning my sour soil and tender my thanks
to those  who responded. Another associated question. I want to plant half a
dozen blueberry bushes. What I know of my soil, it is alkaline. How do I
create an acid soil which is apparently required for blueberries?
Alistair

 
"Alistair Macdonald"  wrote

A raised bed, dig out the soil from an area, put scaffold boards or similar
around it and fill with ericaceous soil so it is above the surrounding soil,
plant your Blueberries in that (underplanted with cranberries perhaps?).
Your problem will be watering, if we continue to get this sort of summer,
they cannot take hard tap water and will need rainwater, can you collect and
hold enough?

--
Regards
Bob Hobden
17mls W. of London.UK

 Bob,
Encouraged by your guidelines on the cultivation of blueberries I have
bought half a dozen and will soon be planting them. They are about 2 feet
tall, mostly bright green foliage and  branches with a few small bunches of
berries. What rules do I adopt about pruning?
Alistair