Pepper wilt again

Yesterday, I kept the water on all morning to spray the courtyard gardens, including the pepper/herb garden. Today, I observed another bell pepper succumbing to wilt, and I’m now convinced that it’s a fungus that has infected both soil and plant. I’m not sure if it’s already too late but I’ve dumped a cup of water with some hydrogen peroxide on it to see if it can be rescued. I’ve also noticed that the Thai chili pepper is starting to display yellowing leaves on the lower extremities. I gave it a dose of peroxide water as well. Only time will tell if the treatment works. I’m considering spraying a peroxide solution too but given the heat, I’m afraid of burning the leaves.