It's an all season beautiful trek. In all seasons, you will have a different experience of the same trek. If you want to see and play with snow, you can go in any month from November to March, it is said that it is better to go in January February or even March because by that time due to snowfall, the whole trail would be covered with snow. If you go in spring, i.e., April May then you will experience the sky changing it's colour from blue to orange to pink and so on. If you go in summer, June - August, then you will experience all the greenery in front of you with birds chirping around. And during the autumn season, you will have a different experience.