Can I move my crop plan from a spreadsheet into Heirloom?

Yes, and faster than retyping your spreadsheet: there is no file import, but most of the numbers are already in Heirloom, so you only enter your plantings.

Heirloom’s crop catalogue already holds the growing data of 265 crops, such as days to maturity, spacing and harvest window. When you add a planting, those values are filled in, and you change only what differs on your farm.

A succession is one entry, not ten rows: in the planting window, enter the Number of plantings and the Time between plantings, and Heirloom creates them all at once.

The steps are in Add a planting and Plan a succession.