Turning empty land into agricultural land for tax purposes

In light of the possible upcoming changes in property tax rates,  what would one need to do to have land classified as agricultural by the land department.

For example, use the land for planting banana trees, papayas and organic vegetables.

Would 2 Rai of land be considered big enough? 

Is there a requirement in density of the trees, type of irrigation, minimum revenue, or other factors that need to be in place for it to be considered agricultural land by district officials when assessing land for property tax purposes?

Thank you in advance.