Ash is sprinkled all over the field before ploughing the land for better yield of cumin crop.
Crop: Cumin
Crop Family: Umbellifers
Crop Scientific Name: (Cuminum cyminum)
Crop Vernacular Name: Jeera, jeeru, jeere
Formulation: Ash
Ingredients: Ash
"Fly ash, being a good soil ameliorant & source of secondary plant nutrients as well as micronutrients can significantly improves the physio-chemical properties (like B.D., W.H.C., pH, CEC, free lime etc.)."
http://coal-ash.co.il/sadna14/Kumar_FlyAshUse.
"Farmers in Rajasthan practices the application of biodynamic preparations and organic manures to increase the production of cumin (Cuminum cyminum L.)"
http://www.isss.ind.in/pdf/journalVolume1/paper-2Dr.S.K.sharma.pdf
"The grain yield was significantly improved with the interventions given in demonstrations as compared to farmers’ existing practices."
http://krishi.icar.gov.in:8080/jspui/bitstream/123456789/19405/1/IJSS%20Glal.pdf