The daffodil plants grow best in a soil having a pH range of 6.0 to 6.5. If the soil in a garden has a pH of 4.5, which substance needs to be added to the soil in order to grow daffodils?
(a) salt
(b) lime
(c) sand
(d) compost
Option b, Lime
Your soil is acidic and you would like to change the pH so that it is less acidic. The universal advice is to add lime to the soil ie liming your soil. Lime is alkaline and it will neutralize the acidity of the soil and make it more neutral.