Various state delegations from Jharkhand, Jammu and Kashmir, Maharashtra and Himachal Pradesh had had visited Haryana to study the project, the spokesman said.
The states of Orissa and Rajasthan had also collected details about the scheme from the Agriculture Department in this regard.
Under the project, soil specimens were collected and examined by scientists for their mineral composition in soil testing laboratories in order to determine the appropriate fertilisers to enrich the soil.
Soil health cards were then prepared on the basis of the tests in the laboratories and delivered to the farmers, the spokesman said.
The Agriculture Department had also started an SMS service to inform farmers to collect the cards immediately after they were prepared.