The question is about how smallholder farmers can have soil sampling and testing services at reduced or affordable costs
Your question connects so well with soil test- based fertilizer recommendation in small farms where farmers don't have so much access to soil testing. In that case , farmers can follow the fertilizer prescription of those fields in that region which are known for high productivity. Can also take some clues from region specific demonstration trials on fertilizer response..
By reviewing the historical data of given soil, we can averagely predict how changes are taking place in pH value, nutrient content, and other soil parameters. or can use a biomarker to balance some requirements.
Thank you
Thank you Anoop Kumar Srivastava and Akeel Mohamed for your insights
They need to collaborate with university students around the area to use soil from them when doing their practical in agriculture related courses.
I agree with Anoop and add that soil analysis could be less frequent and foliar analysis more frequent
Generally, soil being derived from the parent geology would be more or less uniform over a certain area of even agricultural fields. Since soil testing would have been already undertaken by a few in the area, this information could be made available to the small holding farmers.
However, since there has been a lot of awareness on the fertilizer application over a period of time, many seem to be opting for organic fertilizers which many customers also prefer. Therefore, one needs to be careful in recommending fertilizers depending upon mainly the composition.