pH and Neutralisation


To keep growing crops on the same soil you need to add fertiliser containing compounds of nitrogen and phosphorus. This is because these elements are taken from the soil by the plants as they grow. Another change also happens in the fields - the soil becomes more acidic. This causes crops to give lower yields. The soil has to be neutralised using lime or powdered chalk to make it more fertile.


To 'lime' a field costs money and farming is a business, so only the correct amount of chemical should be used to lime each part of the field.

Farmers use soil pH kits to make maps of their fields.

We can use a pH probe, connected to a TI-Nspire Lab Station, to collect and save the data.

Which are the main parts of the field that are most acidic?

Work out the area of the field that is alkaline.

Read what the experts say about liming fields:

Think what the cows might have to say by viewing this YouTube liming for Maize video!