Hello Sir,
The cost generally varies and depends on whether you would like to prepare organic manures in your farm, or purchase from outside, Or go in for insitu green manuring. If you are purchasing from outside also depends on what you buy, FYM, vermicompost and there are many organic manures available in the market. For complete information contact Kulandaisamy, a progressive farmer and owner of TARI high-tech horticulture farm, at Marunkulam. They have acres of organic banana farm.
Regards
Ashwini S