The Harvests module includes a date filter that you can use to view harvests from any range of dates. By default the filter is set to "Today", and only shows harvests that have been brought in today. To change the filter, press on the date filter at the top of the Harvests screen.
This opens a menu of date filter options, which include several preset options as well as the option of using a custom date range.
Select the filter option of your choice by clicking on it.