For the "from" dates, just enter the date when your mother became a homemaker (basically, the date when she finished her last job or her last educational institution, even if it was many years ago). For the "to" date, enter the date when you're applying for the visa.
Make sure to cover at least 10 years of history with your entries.
Important: The form instructions state that "if you are retired, give information about the 10 years before your retirement." There is a fine line between "homemaker" and "retired". If I were you, I would err on the side of caution, and provide information for 10 years before she became a homemaker, even if this takes you back many decades. For example, if she became a homemaker in 1997, provide her full activity history (jobs, education) from 1987 to the present day, without leaving any gaps.