Soil pH is a measure of hydronium ion (H₃O⁺, or more commonly the H+) activity in the soil solution. Activity is similar to concentration in non-salt affected soils.

Soil pH influences many facets of crop production and soil chemistry, including the availability of nutrients and toxic substances, activities and the nature of microbial populations, as well as the activities of certain pesticides.

Soil pH determination

Three soil pH ranges are particularly informative:

1. A pH < 7,0 indicates the presence of free acids, generally from oxidation of sulphides. These soils are called to be acidic.
2. A pH = 7 suggests the likely occurrence of H+ and are called neutral.
3. A pH > 7,0 indicates the presence of CaCO₃ and these soils are called to be alkaline.

Lime requirement of general soils

This is the amount of a base (in practice, lime or calcium carbonate) needed to neutralise enough of the exchangeable acidity to raise soil pH to a desired value that is more suitable for crop growth.

In most soils it has been noticed that pH tends to increase with depth. This is because the upper horizons receive maximum leaching by rainfall, and by dissolved carbonic acid and organic acids which remove metal cations (for example Ca++, K+, Mg++) and replace them with H+ ions. Lower horizons are not so strongly leached and, in fact, in dryer areas may accumulate calcium and other materials removed from the upper soil.

ETG supplies all the high quality products that farmers can use to neutralise their soils to the appropriate pH that is needed by the crops planted. Their range includes fast acting lime, such as their micronized lime. 

Unique characteristics of ETG’s micronized lime:

• Faster reaction time due to micro particle size.
• Smaller particle size which gives larger reaction surface
• 5 kg of micronized lime(<10 micron) does the job of 2 metric tonnes of conventional lime (0,7 – 1,2 micron)

• Ease of application through any form of agricultural irrigation such as overhead sprinklers or centre pivots.
• Application at any time of the year as well as when alkalinity and acidity conditions are observed while the crops are actively growing.
• Can be applied with any type of farming (conventional, no till, minimum till, leased land or pasture) or growth medium.
• Diminished volumes to be handled results in savings on transport costs, time and equipment.