The season length is defined in terms of temperature and hours of sunlight: rainfall affects the suitability, but not the season length (see documentation).
The suitability is defined in terms of both temperature and rainfall (the current text refers to rainfall only).
The Climate Data Store link goes to the wrong dataset on both pages .. it should go to https://cds.climate.copernicus.eu/cdsapp#!/dataset/sis-health-vector?tab=doc
The season length is defined in terms of temperature and hours of sunlight: rainfall affects the suitability, but not the season length (see documentation).
The suitability is defined in terms of both temperature and rainfall (the current text refers to rainfall only).