A productive and sustainable agricultural system is fundamental to the wellbeing of a nation and a cornerstone to its development. In most parts of sub-Saharan Africa, soils are the limiting factor to agricultural production, often being over-exploited.
Because of the high cost of transportation, many small-scale farmers in remote regions cannot afford to buy fertilizers. The use of locally available mineral resources along with waste products has been tested and successfully implemented by the Mintek Small Scale Mining and Beneficiation Division (SSMB) to the benefit of the farmers who have made use of it.
BIOMIN™ is a class of low-cost soil ameliorant that is made from a combination of minerals and various biological waste products. Each region identified for possible production and the application of BIOMIN™ is analysed to see what plant nutrients are lacking in the soil and what valuable raw material inputs are available in the area to use for the production of the appropriate soil ameliorant.
Examples of raw material inputs are:
- Limestone that can be heated to form burnt or unslaked lime,
- Ash from various industries such as burnt sugarcane or Fly ash from coal-fired thermal power stations and
- Organic waste products that contain nitrogen.
The latter could be a waste stream from a sugar mill, cattle and chicken manure or even sewage sludge.
The recipe includes combining the ingredients in a ratio suitable for the area. The burnt lime heats up causing all pathogens from the manure to be destroyed. The soil modifier is therefore sterile and perfectly safe for use in gardens and on lands.
When BIOMIN™ is applied to the soil the following results are obtained:
- The added micro and macro nutrients lead to increased plant growth and yields
- There is improved organic matter that adds to the biological activity in the soil
- Increased plant growth should lead to decreased soil erosion
- The pH of the soil increases
- There is an increase in the ability of the soil to retain water.
BIOMIN™ has been made and applied to soils in a number of places in South Africa. A Pilot project is being run at Marble Hall where the farmers have found an increase in yield over the control plants. Because Biomin is slow to release all its nutrients, the Biomin fertilized plots are still flourishing
ROCK FLOUR is made by grinding basic igneous rocks, such as basalt. These rocks contain many trace elements that can be utilised by plants, contributing towards healthy growth.