There are three reasonable options:
1. You prepare a shape file (*.shp) with the polygons and a column with recharge for each period. Then choose Join - Polygons - Load the file. In the header of the right box in the upcoming dialog ('Parameter Association'), switch to 'time levels', enter your time stages after clicking on the 'Time levels' button, and link the columns from the shape file to the time levels.
2. You prepare a time series (powerfunction) for each polygon and a polygon file (e.g., shape file) with all the zones. In the polygon file, add a column with the corresponding number of the powerfunction. You can then import the data via Join - Polygons - Load the file. Link to the recharge parameter and choose 'Powerfunction ID'. The blue link indicates that you import time-series IDs.
3. Prepare a distribution for one of the time stages as time-constant recharge, then go to T-List and import that distribution for a certain time stage. Repeat the process until you have all the time stages.