The purpling along the leaf edges is the characteristic deficiency symptom of

Solution (By Examveda Team)

The purpling along the leaf edges are the characteristic deficiency symptom of Phosphorus. It mostly occurs on the underside of the older leaves due to the accumulation of the pigment, Anthocyanin.
Phosphorus is important for plants to promote photosynthesis, protein formation, seed germination, bloom stimulation and budding.