Step 1: Understanding Article 356.
Article 356 deals with the imposition of President's Rule in a state when the state government is unable to function according to the provisions of the Constitution. This happens when the President is satisfied that the state's constitutional machinery has failed.
Step 2: Initial time period.
The Constitution clearly mentions that President's Rule can first be imposed for a period of 6 months. This is the maximum initial duration allowed without parliamentary extension.
Step 3: Extensions possibility.
After the initial 6 months, it can be extended every 6 months, but only up to a maximum of 3 years with conditions such as National Emergency or Election Commission certification. However, the question asks only for the initial period.
Step 4: Conclusion.
Thus, the initial duration for which President's Rule can be imposed under Article 356 is 6 months.