Question

what should be added in the soil when it is too acidic or too basic

Answer 1

when soil is too acidic we can add limestone...
when soil is too basic we can add organic matter such as manures...

Answer 2

Answer:

If the soil is too acidic than we can add Quicklime or Slaked lime to neautralise the excess acid present in the soil.

Manure or Compost should be added to the basic soil because manure releases acid that neautralise the basic Nature of the soil.