Mar 3, 2018 - 8:51 PM
in reply to dinetrsp
Well I agree the places Lucas suggests are your best bet. If your primary goal is to see green valleys then head South.
The Centovalli between Locarno and Domodossola certainly has many valleys and pastures but how green they will be at the end of March I can’t say.
That route combined with the Bernina Express would give you a wide circle of Switzerland and give you the best chance to see what you are after plus the snow-covered Alps which attract most people.
Where are you arriving/departing Switzerland?