To whom, in the cage of confinement, the memory of Gul's bloom is now a mere sustenance for life. (Meaning: The memory of Gul's beauty, confined in a cage, is now barely enough to sustain life.)

This couplet is a profound commentary on the harsh realities of life versus the sweetness of memory. Mir Taqi Mir suggests that when a person is trapped (in a cage or difficult situation), the luxury of remembering beautiful things or loves is lost. The focus shifts entirely to mere survival—to the basic necessities of life. It's a poignant moment where the poetic ideal meets the brutal reality.