Can anyone let me know if this is sunburnt or is this plant sick? I have it at our patio on the east and 2 days a goat noon, the sun was shining on it as it was too near the edge. I have moved it farther in and noticed the leaf turning black on one area.
Looks more like an infection to me. Burn tends to go from green to brown, not black, and the edges are more defined, not a peripheral yellowing like that. I would guess that water stood on that part of the leaf and allowed a fungus to grow.
I'd cut off the outer half of the leaf - anything containing any discoloration, and dust the wound with cinnamon powder.