Gulzar, one of the best ever poets of India (at least to me), was born Sampooran Singh Kalra. That is, Gulzar was a Sikh, with a beard and a Pagdi. Yes, I've even seen the old picture of a young Gulzar in beard and turban.
Gulzar was his pen name he had started writing with since very beginning of his career, or say even before that.
The meaning of 'Gulzar' is blossoming/blossomed.