When I started looking for this information, numerous articles claimed the following:
The AGRO-CLIMATE Planning Commission advocated for agro-climatic conditions in agricultural planning.
The country is divided into 15 agricultural zones based on soil type, temperature, warmth, rain, and rainfall patterns.
Western Himalaya, eastern Himalaya Ganges Plains and hills to the east Middle hills, west hill, south hill, hilly east coast, hilly west coast Gujarat's plains and hills.
You can access GIS layers for all 15 agro-climatic zones of India from the Indian Council of Agricultural Research (ICAR) website. The GIS layers can be found in the Resources section of the ICAR website.