From the left menu>Federal>Income & Expenses>
Scroll to your Farm Income and Farm Rental and click Edit/Add>
Answer the Income questions again to get to the Farm Summary and click Edit>
Scroll down to Farm Expenses>Common farming expenses and click Update>
Scroll to Mortgage Interest to adjust the value>Continue and follow the rest of the prompts.
It does not appear that it otherwise has its own Form 1098 section like the individual section.
