Ive just broken up a concrete shed base (around 1.5m x 3m) and want to use the soil underneath for planting. Obvioulsy the act of breaking up the concrete has meant that a lot of concrete rubble and dust been thrown into the soil.
the soil was quite compacted, i removed as much of the concrete and stones from the top, then forked it over to about depth of a garden fork.
At this stage measuring the ph it was heavily alkaline. This could be the natural ph, or it could be due to the concrete.
It was still quite compacted, so ive added sand to it. Also added a lot of well rotted horse manure.
How do I go about reducing the ph, to make the soil slightly acidic?
will the concrete mixed in the soil continue to cause problems no matter what i do? Or will adding acid to the soil balance out things and fix the problem?
also what duration of time do i need to wait before thinking of planting in it?
many thanks for any assistance.